a windows 8 bug, maybe. Certainly affecting windows 7 x 64 when it was working just great with WB 7.xx. I've already told stardock about this many month ago since the first 8.xx and it's still there.
For the transparency, my skin has an active/inactive state, visible with my previous WB installation. With the 8.12, the transparent part of the inactive state is just gone, there is no transparency at all. Obviously something has changed.