At present a PDF Form created in LifeCycle are no longer able to be edited in latest versions of Adobe Acrobat Professional (not Reader) unless the Form was created in an older version of LifeCycle released with Adobe Acrobat 8.0 (and possibly 8.1)
In these versions of LifeCycle Adobe created and saved both a "new" style form and the "old" style form data in the same package.
If this is the case then you can use the situation described above to open the form in (old) version of LifeCycle, save it as a "static PDF Form" (rather than dynamic) and use the public domain pdf tool to strip the "XFA" header.
Then when you open the form in Adobe Acrobate (not reader) it will not complain about needing to open it in LifeCycle but also allow you to edit it and have access to scripts etc.