Using Composites and Lines

I have a requirement to create flow charts(similar to attached).
To achieve this, the nodes(GWT composite) and lines should be displayed together.

So the nodes(GWT composite), will display the table with multiple rows of textbox, dropdowns etc.
And the lines will connect the nodes.

The NodeGraphWidget addon works perfectly for me if instead of text nodes, composites can be displayed.
Can the NodeGraphWidget addon be used to display a composite as a Node?