In trying to make a demo of a Government of Canada Planning Application, I struggled with building a hierarchal Form to allow data capture at 2 or more levels in the hierarchy. This is what I built and how I did it.
This application allows a user to enter the departmental commitment and the associated milestones. To make this I had to use a form library. I first tried using lists but there was not enough flexibility. Steps are as follows
Create your fields and groups by hand. These are repeating groups and milestones a nested group. This field set was created using the UI on this form, click add on the drop down arrow is the trick.
On the form, remove all the tables and headers and add your own tables by hand. Then add a repeating section to the form and bind it to the CommitmentsGroup.
To create the repeating table of Milestones, highlight Milestones in the fields list and click insert repeating table.
Then to add the commitments fields manually create a table above the repeating table and drag the commitments fields to the form and that is it,