OK, I removed all exceptions in WB Config having to do with Yahoo Mess.
I uninstalled YM with an advanced uninstaller.
I reinstalled YM.
Now the windows opened as a result of clicking a link is back to normal, but some dialogs opened in YM are still not skinned, and I'm beginning to think it IS WB related.
I've been using this version of YM a long time and have never had this problem.