Ok, so I've been playing through story mode (since I can't export yet. Grrrrrr.)
My wife and I were playing last night, and we only got 4 stars on the first challenge (seeing as she wasn't familiar with the song Tick Tick Boom). We went back and re-played it and got 5 songs, but we never got credit for going back and getting the 5th star. So, my star count is at 104, despite the fact that I have now 5 starred everything up to this point.
Has anyone else had this problem?