In fact, none of the theme's bitmap actually have the color key and are not transparent anyway.
ALPHABLEND_BINARY is only used when the property TMT_GLYPHTRANSPARENT or TMT_TRANSPARENT is TRUE. Which theme part and state is the application trying to draw? If the theme part is not transparent then we should probably not set TMT_TRANSPARENT or TMT_GLYPHTRANSPARENT to TRUE.
while all the time spent in processing LB_ADDSTRING in listbox control for updating scroll bar.
Is the listbox from Wine's comctl32? Can this be fixed in comctl32 instead?