Okay. I tried to test the "not gaining Imperial Authority" thing by going to war with Denmark+Burgundy. After a long and bloody war, the HRE, Duke of Nassau (me) was finally able to liberate Luxembourg from Burgundy, and then, after even more bloodshed on the Jutland peninsula, freed three imperial provinces from Denmark (Holstein, East Frisia, Bremen).
Total IA gained?
0
WAD?
p.s. I think this may have to do with the system trying to calculate the IA gained based on the old "base tax" whereas there should be something now based on total development in the province. That may be where the bug is.
Also, one last thing. Even though I have 80 IA, I have a grand total of only myself voting for the first reform. I think there's something bugged with the voting as well. Everyone pretty much loves me (I've been a kindly emperor). But no one wants to vote for reforms. Not even my allies. I don't get it.