You can slice him, you can dice him, but Revan will ALWAYS be back!
So yeah, yesterday I spent ~7 hours stress testing the Upgrade script, and I weeded out 99.9% of all the problems with it. What remains is some after-upgrade bugs (No Permissions screen seems FUBAR for some reason), which I will spend today sorting out.
EDIT: And now fixed.
Havn't made any progress on the Battle Arena yet, though that will come in good time.