I also have the mouse-over error. I'm stuck before the massage with cousin, can't retrieve Anna either.
The replay mod seems to make that error, i remove the mod and start a new save and didn't have, i didn't play long but at the start of the game no error.
Edit 1: Well the night of the first day the "heart" works fine for me, i can mouse over and see the stats, the second day the error starts, let me try removing the IC mod too.
Edit 2: Yep, the mods are causing the problem, extract you game again or download if deleted the file, go to users\pcname\appdata\Roaming\RenPy and delete my cute roommate folder and also my cute cousin if you have there too, start a new game and it will work, do not install any mod, after you complete the game you can put the replay mod to see the scenes again.
tags : mouse problem , heart bug , heart crash , mouse over .