http://bugs.winehq.org/show_bug.cgi?id=28646
--- Comment #20 from Dan Kegel dank@kegel.com 2012-05-27 15:07:52 CDT --- I've extracted the icon that has the problem from the demo program; it's at http://kegel.com/wine/bad.ico The areas that are improperly black on Wine are transparent when viewed in Gimp.
spy++ shows that the affected icon has class XTPToolBar, which is part of CodeJock's commercial component library.
Tanner's S-Edit (http://www.tannereda.com/t-spice-pro), and probably lots of other commercial software, also uses that component and is affected by this problem.