Please update to the WB 7.09c build that went up today and see if this helps or not.
1°) Well, for me things are different that for RedneckDude and are giving a nice improvment (not complete as you'll see 
)
IE 7 toolbars lines are no more blacked but "only" the part which is called (i think) rebargripper
Significant example to see the trouble, is with LK WB (by Duopixart): (but other skins are doing the same)
(same as in post #1, click on the image, then click on "voir la taille réelle to see the real sized image)
BUT, as the previous "black" trouble was systematic, now the blacked rebargripper are appearing or not when launching IE 7 
and N.B.1, N.B.2 & N.B.3 mentionned in post #1 are still relevant .
2°) That was the news for the "black" trouble, BUT i found out another trouble now with StartMenu (which was already existing with both WB 7.09a betas but not with WB 7.09) and relative to the UserIcon image for skins allowing one
Here are two examples of what's going on (first still with LK WB, 2nd with Buuf OS WB:
& 
As far as i could check (but i can be wrong) it seems to me this trouble comes when a UserIcon background image is not defined and / or the margins not correctly set in the skin (but with same skins, UserIcon is correctly displayed with WB 7.09 
)
N.B: using or not Blur on Startmenu doesn't change anything
Hope you'll get enough elements to correct those troubles
