I am running beta 56(3823) on 10.5.6 and having the same issue with the third pane not showing up when I want to use "Move to. . ."
I typically use this in conjunction with using command-G to "get" the item selected in the Finder so that I can move it somewhere else. I haven't used "Email To . . .", but after reading this post I tried to. I don't have that command available when I invoke QS, nor is it an option in the prefs. I, too, am looking to fix this since "Move To . . ." was a stand-by QS action of mine.
