Hello all,
Quick update on this for whom it may concern.
It appears this happens with transparent areas surrounding the Start Menu in certain WB skins, which can happen with the Mica effect on. Skins without transparent areas surrounding the Start Menu don't appear to be affected. At this time turning off the Mica effect seems to be the best solution for effected skins.
In any case I've logged this so we can keep an eye on it.
Internal reference: ODNT-8745
Thanks to everyone,
Adam McGuinness
Stardock Customer Support Specialist