Revolving under a mask
I've got a composition in which I have a friend of mine doing some scratching on a record deck, then a layer of some other footage which has been re-sized, and tilted using the basic-3d effect and has an eliptical mask, which makes it the same size as the record being scratched.
It also has another layer of the guy scratching over the top with the record keyed out so it looks like he's scratching with the moving clip.
OK, if anyone is following this, I now need to rotate the clip underneath the mask so it looks like he's scratching it back and forth, but if I try and key-frame the transform>rotate function, it rotates the whole layer, mask included, which looks a bit odd as it's skewed by the 3d effect.
Could anybody suggest how to rotate the video behind the mask, so it looks like the record?
I expect (well, hope) its something trivial that I've overlooked.
Panasonic SD9, Panasonic NVGS-75, Canon MV600i