http://bugs.winehq.org/show_bug.cgi?id=17856
--- Comment #9 from Charles Davis cdavis@mines.edu 2009-11-13 08:31:40 --- Yup. The depths are mismatched. The depth of the Visual is 24, but the depth of the pixmap is 32.
That's funny, because SolidWorks asked for a 32-bit format. I suspect that in the XVisualInfo structure, the depth member doesn't include alpha bits.