http://bugs.winehq.org/show_bug.cgi?id=15346
--- Comment #4 from Marc Menghin marc.menghin@gmail.com 2008-12-06 08:43:39 --- I can confirm this. The problem seems to me that while moving the windows very fast it gets wrong positions (or position changes). This leads to the result that the windows get places off screen. It did not happen so far on slow movement of the windows.
So windows are still there and work fine, they are just outside the screen.
How to reset the windows is explained here: http://forums.winamp.com/showthread.php?threadid=164598