The FAM 2.0 version that is currently on the wild is an early Alpha that I sent to a few people for testing. It wasn't intended for public release.
The bug you mention is not a bug. Account renaming had not yet been fully coded by the time that version got released. That's why it doesn't work.
As of late, I have more free time available (I'm even ingame). I'll see if I'm able to implement the remaining stuff on the program (account creation, etc), and deploy a 2.0 version that works properly.
(If you find any mistake in my English, please let me know via a PM)
(Really, I speak terrible English, so please, tell me if I make mistakes. I'd like to improve it a bit )