https://bugs.winehq.org/show_bug.cgi?id=48965
--- Comment #7 from Marko Friedemann mfr@bmx-chemnitz.de --- Well, there's two things that might be relevant.
I have been running stuff for years with "wine explorer /desktop=$name,$resolution $executable" That way, they are running within their own "virtual desktop" and are not minimized when I alt-tab out. This might be in conflict with that particular key remapping function, because from the log, it appears it is kicking in every time, whereas from the comments, I assume it's not meant to do that.
I also have a patch that makes Unity's global menu disappear.
I didn't have much time to further test, have just been using an older build with all my patches. Will see if I can test with a fully stock wine without the explorer option.
M.