I have an idol with the trait that makes negotiations for photoshoots never fail, and while it shows that it succeeded (+10% etc), the amount of money they're being paid still goes down.
This actually seems to happen regardless of whether or not I have the idol - the amount displayed after you hit negotiate, whether you succeed or fail, is often incorrect and doesn't match what it should be.
Some more:
If I'm dragging an idol to socialize and that idol is automatically pulled into another room (practice, styling etc) the idol's portrait gets stuck on the mouse cursor. Nothing breaks and you can drag a different idol to make it go away. Edit: "Socialize" gets stuck on display on your room, though, and that doesn't go away.
Switching from Compact view to Full view for idols will add an extra copy of the idols list every time (so you get to the last idol and under it will be the whole menu including the "new group" button).
Compact view does not show idols in sister groups.
Canceling a practice/styling/doctor session by clicking on the idol portrait or using the idol menu will make the staffer idle. Doctors are especially buggy since their auto actions are still toggled on, and so you need to toggle a new action or deselect an old one to make them work again.
The "no critical failure" card for concerts doesn't seem to do anything at all.
Trying to release a non-election single with the election concert ready to go triggered the concert music and locked the game. Upon closing and reloading, it automatically started the concert with buggy (white square) idol portraits and didn't release the non-election single.
Edit:
More:
You can't set an automatic style in the "auto practice" menu for idols (it doesn't select the option and will de-select any other options you have).
If you click promotion/performance/spa treatment right as the day is about to end with an active queue, it replaces the next item on your queue.
If you remove items from the queue when it's full, you can't queue up additional things until the next day.