Bringing in some additional information from a PM with @aramirez (who is also looking to upgrade to Platform 2.x now that Sync 2 will support this):
Per this other thread, Daniel has done a fix for this, it just needs to be tested by some real user: Cohort builder error on openmrs 2.1.2. - #13 by dkayiwa (i.e. you’ll be able to go all the way to 2.1.
I would expect that Address Hierarchy and IDGen should work (because PIH has already tested these in preparation for their upgrade), and XForms should work (because it’s part of the reference application).
I don’t know about custombranding (I could imagine it getting broken when we pulled the UI into the legacyui module with platform 2.0), but if it’s working for you, great!
For reportingcompatibility, if you find any errors beyond the one discussed above about Cohort Builder, then please share.
Sorry that we dropped the ball when you pointed this bug out last year. I just asked you a question on docs and resources migration - #6 by darius (which will tell us what kind of fix is appropriate).
I don’t know the answer to this, since as a developer I’m not using tomcat. I’m sure someone else can answer this though.