Good deal. As soon as I can snag a functional action bar add-on, I'll be able to give it a full test. Thanks. :)
Dominos has a MoP ready beta (Dominos MoP Beta). Just make sure the "Always Show Action Bars" (or similar wording) option is off in the default (Blizzard) action bar options, or you'll be seeing "shadow bars".
I just figured the author would have a clue, and since I wasn't in a crashing hurry I'd just ask. As it turns out it makes absolutely no difference at all. Masque just doesn't work (for me, anyway) in the MoP Beta. Yet.