The main issue is fixed indeed, but several win32k blt/blend functions have
problems with one of the two possible 16 Bit pixel formats. This can be seen
in VMWare taskbar icons in 16 Bit.
Bitblt seems to handle them correctly - so the copyimage hack works around
this remaining bug. See latest comments in bug #2225 for more info about
this.
Best regards
Gregor Schneider