I specifically called Bottomline on this very subject and they confirmed to me that there should be no issues with CreateForm. We are using CTIS 7.0 as we had to move from version CF 3.2 with E1 9.10, but 9.1.5.2 should be usable with CreateForm 7.0.
If you are moving from an older tools release and are using CF 3.2, then yes. JDE PDF output will not work with version 3.2. We had to migrate to CTIS 7.0 when we went from 8.12 to 9.10.