http://bugs.winehq.org/show_bug.cgi?id=31832
--- Comment #3 from Aric Stewart aric@codeweavers.com 2012-10-02 12:16:16 CDT --- (In reply to comment #2)
Interestingly, unlike regedit, notepad does close normally. I've first tried on it to check if the bug affects non-games, but notepad appears to be an exception from the bug :)
I am unable to reproduce this on my Mac at all. Both notepad and regedit are closing as expected.
Maybe a +imm,+win log?