Unable to install widget

Hi, I am new to vaadin so apologise for newbie question. I want to use this add-on for my app, I setup my app via Maven and I installed jar file as well as set dependency for the POM. But after that, when I tried to compile the widgetset I got the following errors, even if I setup a new project via vaadin wizard on Eclipse and copy the jar file manually, the errors are still the same, what did I do wrong? thanks:

Compiling widgetset uk.co.healthsolve.widgetset.CollectconsentWidgetset
Updating GWT module description file...
Jul 20, 2012 6:49:05 PM com.vaadin.terminal.gwt.widgetsetutils.ClassPathExplorer getAvailableWidgetSets
INFO: Widgetsets found from classpath:
	com.vaadin.terminal.gwt.DefaultWidgetSet in jar:file:/Users/Dudu/.m2/repository/com/vaadin/vaadin/6.7.1/vaadin-6.7.1.jar!/
	org.vaadin.hezamu.canvas.widgetset.CanvasWidgetset in jar:file:/Users/Dudu/.m2/repository/org/vaadin/addons/canvaswidget/1.1/canvaswidget-1.1.jar!/
	uk.co.healthsolve.widgetset.CollectconsentWidgetset in file:/Users/Dudu/Documents/workspace/CollectConsent/src/main/java

Jul 20, 2012 6:49:05 PM com.vaadin.terminal.gwt.widgetsetutils.ClassPathExplorer getAvailableWidgetSets
INFO: Search took 6ms
Done.
Starting GWT compiler
Loading inherited module 'org.vaadin.hezamu.canvas.widgetset.CanvasWidgetset'
   Loading inherited module 'com.google.gwt.widgetideas.GWTCanvas'
      [ERROR]
 Unable to find 'com/google/gwt/widgetideas/GWTCanvas.gwt.xml' on your classpath; could be a typo, or maybe you forgot to include a classpath entry for source?
   [ERROR]
 Line 6: Unexpected exception while processing element 'inherits'
com.google.gwt.core.ext.UnableToCompleteException: (see previous log entries)
	at com.google.gwt.dev.cfg.ModuleDefLoader.nestedLoad(ModuleDefLoader.java:262)
	at com.google.gwt.dev.cfg.ModuleDefSchema$BodySchema.__inherits_begin(ModuleDefSchema.java:495)
	at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.google.gwt.dev.util.xml.HandlerMethod.invokeBegin(HandlerMethod.java:230)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.startElement(ReflectiveParser.java:274)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(AbstractSAXParser.java:501)
	at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(AbstractXMLDocumentParser.java:179)
	at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.emptyElement(XMLDTDValidator.java:788)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(XMLDocumentFragmentScannerImpl.java:1343)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2756)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:647)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:511)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:808)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:119)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
	at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.parse(ReflectiveParser.java:331)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.access$100(ReflectiveParser.java:48)
	at com.google.gwt.dev.util.xml.ReflectiveParser.parse(ReflectiveParser.java:402)
	at com.google.gwt.dev.cfg.ModuleDefLoader.nestedLoad(ModuleDefLoader.java:280)
	at com.google.gwt.dev.cfg.ModuleDefSchema$BodySchema.__inherits_begin(ModuleDefSchema.java:495)
	at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.google.gwt.dev.util.xml.HandlerMethod.invokeBegin(HandlerMethod.java:230)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.startElement(ReflectiveParser.java:274)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(AbstractSAXParser.java:501)
	at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(AbstractXMLDocumentParser.java:179)
	at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.emptyElement(XMLDTDValidator.java:788)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(XMLDocumentFragmentScannerImpl.java:1343)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2756)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:647)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:511)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:808)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:119)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
	at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.parse(ReflectiveParser.java:331)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.access$100(ReflectiveParser.java:48)
	at com.google.gwt.dev.util.xml.ReflectiveParser.parse(ReflectiveParser.java:402)
	at com.google.gwt.dev.cfg.ModuleDefLoader.nestedLoad(ModuleDefLoader.java:280)
	at com.google.gwt.dev.cfg.ModuleDefLoader$1.load(ModuleDefLoader.java:192)
	at com.google.gwt.dev.cfg.ModuleDefLoader.doLoadModule(ModuleDefLoader.java:308)
	at com.google.gwt.dev.cfg.ModuleDefLoader.loadFromClassPath(ModuleDefLoader.java:151)
	at com.google.gwt.dev.GWTCompiler.run(GWTCompiler.java:162)
	at com.google.gwt.dev.GWTCompiler$1.run(GWTCompiler.java:131)
	at com.google.gwt.dev.CompileTaskRunner.doRun(CompileTaskRunner.java:87)
	at com.google.gwt.dev.CompileTaskRunner.runWithAppropriateLogger(CompileTaskRunner.java:81)
	at com.google.gwt.dev.GWTCompiler.main(GWTCompiler.java:138)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.vaadin.tools.WidgetsetCompiler$1.run(WidgetsetCompiler.java:85)
	at java.lang.Thread.run(Thread.java:680)
   [ERROR]
 Failure while parsing XML
com.google.gwt.core.ext.UnableToCompleteException: (see previous log entries)
	at com.google.gwt.dev.util.xml.DefaultSchema.onHandlerException(DefaultSchema.java:58)
	at com.google.gwt.dev.util.xml.Schema.onHandlerException(Schema.java:66)
	at com.google.gwt.dev.util.xml.Schema.onHandlerException(Schema.java:66)
	at com.google.gwt.dev.util.xml.HandlerMethod.invokeBegin(HandlerMethod.java:240)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.startElement(ReflectiveParser.java:274)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(AbstractSAXParser.java:501)
	at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(AbstractXMLDocumentParser.java:179)
	at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.emptyElement(XMLDTDValidator.java:788)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(XMLDocumentFragmentScannerImpl.java:1343)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2756)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:647)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:511)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:808)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:119)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
	at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.parse(ReflectiveParser.java:331)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.access$100(ReflectiveParser.java:48)
	at com.google.gwt.dev.util.xml.ReflectiveParser.parse(ReflectiveParser.java:402)
	at com.google.gwt.dev.cfg.ModuleDefLoader.nestedLoad(ModuleDefLoader.java:280)
	at com.google.gwt.dev.cfg.ModuleDefSchema$BodySchema.__inherits_begin(ModuleDefSchema.java:495)
	at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.google.gwt.dev.util.xml.HandlerMethod.invokeBegin(HandlerMethod.java:230)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.startElement(ReflectiveParser.java:274)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(AbstractSAXParser.java:501)
	at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(AbstractXMLDocumentParser.java:179)
	at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.emptyElement(XMLDTDValidator.java:788)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(XMLDocumentFragmentScannerImpl.java:1343)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2756)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:647)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:511)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:808)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:119)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
	at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.parse(ReflectiveParser.java:331)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.access$100(ReflectiveParser.java:48)
	at com.google.gwt.dev.util.xml.ReflectiveParser.parse(ReflectiveParser.java:402)
	at com.google.gwt.dev.cfg.ModuleDefLoader.nestedLoad(ModuleDefLoader.java:280)
	at com.google.gwt.dev.cfg.ModuleDefLoader$1.load(ModuleDefLoader.java:192)
	at com.google.gwt.dev.cfg.ModuleDefLoader.doLoadModule(ModuleDefLoader.java:308)
	at com.google.gwt.dev.cfg.ModuleDefLoader.loadFromClassPath(ModuleDefLoader.java:151)
	at com.google.gwt.dev.GWTCompiler.run(GWTCompiler.java:162)
	at com.google.gwt.dev.GWTCompiler$1.run(GWTCompiler.java:131)
	at com.google.gwt.dev.CompileTaskRunner.doRun(CompileTaskRunner.java:87)
	at com.google.gwt.dev.CompileTaskRunner.runWithAppropriateLogger(CompileTaskRunner.java:81)
	at com.google.gwt.dev.GWTCompiler.main(GWTCompiler.java:138)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.vaadin.tools.WidgetsetCompiler$1.run(WidgetsetCompiler.java:85)
	at java.lang.Thread.run(Thread.java:680)
   [ERROR]
 Unexpected error while processing XML
com.google.gwt.core.ext.UnableToCompleteException: (see previous log entries)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.parse(ReflectiveParser.java:355)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.access$100(ReflectiveParser.java:48)
	at com.google.gwt.dev.util.xml.ReflectiveParser.parse(ReflectiveParser.java:402)
	at com.google.gwt.dev.cfg.ModuleDefLoader.nestedLoad(ModuleDefLoader.java:280)
	at com.google.gwt.dev.cfg.ModuleDefSchema$BodySchema.__inherits_begin(ModuleDefSchema.java:495)
	at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.google.gwt.dev.util.xml.HandlerMethod.invokeBegin(HandlerMethod.java:230)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.startElement(ReflectiveParser.java:274)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(AbstractSAXParser.java:501)
	at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(AbstractXMLDocumentParser.java:179)
	at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.emptyElement(XMLDTDValidator.java:788)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(XMLDocumentFragmentScannerImpl.java:1343)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2756)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:647)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:511)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:808)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:119)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
	at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.parse(ReflectiveParser.java:331)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.access$100(ReflectiveParser.java:48)
	at com.google.gwt.dev.util.xml.ReflectiveParser.parse(ReflectiveParser.java:402)
	at com.google.gwt.dev.cfg.ModuleDefLoader.nestedLoad(ModuleDefLoader.java:280)
	at com.google.gwt.dev.cfg.ModuleDefLoader$1.load(ModuleDefLoader.java:192)
	at com.google.gwt.dev.cfg.ModuleDefLoader.doLoadModule(ModuleDefLoader.java:308)
	at com.google.gwt.dev.cfg.ModuleDefLoader.loadFromClassPath(ModuleDefLoader.java:151)
	at com.google.gwt.dev.GWTCompiler.run(GWTCompiler.java:162)
	at com.google.gwt.dev.GWTCompiler$1.run(GWTCompiler.java:131)
	at com.google.gwt.dev.CompileTaskRunner.doRun(CompileTaskRunner.java:87)
	at com.google.gwt.dev.CompileTaskRunner.runWithAppropriateLogger(CompileTaskRunner.java:81)
	at com.google.gwt.dev.GWTCompiler.main(GWTCompiler.java:138)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.vaadin.tools.WidgetsetCompiler$1.run(WidgetsetCompiler.java:85)
	at java.lang.Thread.run(Thread.java:680)
[ERROR]
 Line 19: Unexpected exception while processing element 'inherits'
com.google.gwt.core.ext.UnableToCompleteException: (see previous log entries)
	at com.google.gwt.dev.cfg.ModuleDefLoader.nestedLoad(ModuleDefLoader.java:283)
	at com.google.gwt.dev.cfg.ModuleDefSchema$BodySchema.__inherits_begin(ModuleDefSchema.java:495)
	at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.google.gwt.dev.util.xml.HandlerMethod.invokeBegin(HandlerMethod.java:230)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.startElement(ReflectiveParser.java:274)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(AbstractSAXParser.java:501)
	at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(AbstractXMLDocumentParser.java:179)
	at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.emptyElement(XMLDTDValidator.java:788)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(XMLDocumentFragmentScannerImpl.java:1343)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2756)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:647)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:511)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:808)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:119)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
	at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.parse(ReflectiveParser.java:331)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.access$100(ReflectiveParser.java:48)
	at com.google.gwt.dev.util.xml.ReflectiveParser.parse(ReflectiveParser.java:402)
	at com.google.gwt.dev.cfg.ModuleDefLoader.nestedLoad(ModuleDefLoader.java:280)
	at com.google.gwt.dev.cfg.ModuleDefLoader$1.load(ModuleDefLoader.java:192)
	at com.google.gwt.dev.cfg.ModuleDefLoader.doLoadModule(ModuleDefLoader.java:308)
	at com.google.gwt.dev.cfg.ModuleDefLoader.loadFromClassPath(ModuleDefLoader.java:151)
	at com.google.gwt.dev.GWTCompiler.run(GWTCompiler.java:162)
	at com.google.gwt.dev.GWTCompiler$1.run(GWTCompiler.java:131)
	at com.google.gwt.dev.CompileTaskRunner.doRun(CompileTaskRunner.java:87)
	at com.google.gwt.dev.CompileTaskRunner.runWithAppropriateLogger(CompileTaskRunner.java:81)
	at com.google.gwt.dev.GWTCompiler.main(GWTCompiler.java:138)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.vaadin.tools.WidgetsetCompiler$1.run(WidgetsetCompiler.java:85)
	at java.lang.Thread.run(Thread.java:680)
[ERROR]
 Failure while parsing XML
com.google.gwt.core.ext.UnableToCompleteException: (see previous log entries)
	at com.google.gwt.dev.util.xml.DefaultSchema.onHandlerException(DefaultSchema.java:58)
	at com.google.gwt.dev.util.xml.Schema.onHandlerException(Schema.java:66)
	at com.google.gwt.dev.util.xml.Schema.onHandlerException(Schema.java:66)
	at com.google.gwt.dev.util.xml.HandlerMethod.invokeBegin(HandlerMethod.java:240)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.startElement(ReflectiveParser.java:274)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(AbstractSAXParser.java:501)
	at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(AbstractXMLDocumentParser.java:179)
	at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.emptyElement(XMLDTDValidator.java:788)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(XMLDocumentFragmentScannerImpl.java:1343)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2756)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:647)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:511)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:808)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:119)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
	at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.parse(ReflectiveParser.java:331)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.access$100(ReflectiveParser.java:48)
	at com.google.gwt.dev.util.xml.ReflectiveParser.parse(ReflectiveParser.java:402)
	at com.google.gwt.dev.cfg.ModuleDefLoader.nestedLoad(ModuleDefLoader.java:280)
	at com.google.gwt.dev.cfg.ModuleDefLoader$1.load(ModuleDefLoader.java:192)
	at com.google.gwt.dev.cfg.ModuleDefLoader.doLoadModule(ModuleDefLoader.java:308)
	at com.google.gwt.dev.cfg.ModuleDefLoader.loadFromClassPath(ModuleDefLoader.java:151)
	at com.google.gwt.dev.GWTCompiler.run(GWTCompiler.java:162)
	at com.google.gwt.dev.GWTCompiler$1.run(GWTCompiler.java:131)
	at com.google.gwt.dev.CompileTaskRunner.doRun(CompileTaskRunner.java:87)
	at com.google.gwt.dev.CompileTaskRunner.runWithAppropriateLogger(CompileTaskRunner.java:81)
	at com.google.gwt.dev.GWTCompiler.main(GWTCompiler.java:138)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.vaadin.tools.WidgetsetCompiler$1.run(WidgetsetCompiler.java:85)
	at java.lang.Thread.run(Thread.java:680)
[ERROR]
 Unexpected error while processing XML
com.google.gwt.core.ext.UnableToCompleteException: (see previous log entries)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.parse(ReflectiveParser.java:355)
	at com.google.gwt.dev.util.xml.ReflectiveParser$Impl.access$100(ReflectiveParser.java:48)
	at com.google.gwt.dev.util.xml.ReflectiveParser.parse(ReflectiveParser.java:402)
	at com.google.gwt.dev.cfg.ModuleDefLoader.nestedLoad(ModuleDefLoader.java:280)
	at com.google.gwt.dev.cfg.ModuleDefLoader$1.load(ModuleDefLoader.java:192)
	at com.google.gwt.dev.cfg.ModuleDefLoader.doLoadModule(ModuleDefLoader.java:308)
	at com.google.gwt.dev.cfg.ModuleDefLoader.loadFromClassPath(ModuleDefLoader.java:151)
	at com.google.gwt.dev.GWTCompiler.run(GWTCompiler.java:162)
	at com.google.gwt.dev.GWTCompiler$1.run(GWTCompiler.java:131)
	at com.google.gwt.dev.CompileTaskRunner.doRun(CompileTaskRunner.java:87)
	at com.google.gwt.dev.CompileTaskRunner.runWithAppropriateLogger(CompileTaskRunner.java:81)
	at com.google.gwt.dev.GWTCompiler.main(GWTCompiler.java:138)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.vaadin.tools.WidgetsetCompiler$1.run(WidgetsetCompiler.java:85)
	at java.lang.Thread.run(Thread.java:680)
Widgetset compilation failed

sounds like it is searching for an additional dependency to a Google Canvas package, com.google.gwt.widgetideas.GWTCanvas. Don’t know about your maven setup, or if the pom is correctly set up in the add-on, but you could try to manually add that dependency to your pom.