glad I could help :)
Edit: Hmm, just read your next reply, is that always the case, do all WoW windows always leave a 'phantom' mouse after using mouse broadcasting. If that's the case, having a different key sent over is a must.
I can't say if it's allways the case, but I think I had the same problem when I first implemented my mouseover-healing, and the simplest solution for me was to use a different key (or modifier combination not used in the ftl) to get around it (and don't care about save-mouse/restore-position at all).