Hi Brian,
Unfortunately, the markup generated by Form Builder is considered to be "internal", and isn't documented at that level. When the format changes (and we try to keep it as constant as possible!), we make sure that a form produced by Form Builder in an old version of Orbeon Forms still works in a new version of Orbeon Forms, but we can't make that claim for any code that you might have written by hand.
So I think that you're on the right track: you need to find what works and what doesn't, and for the things that don't work debug the issue and figure how the source needs to be changed. And if course, if there is anything you don't seem to be able to figure out, just let us know!
Alex
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