bag animation

it is very difficult to get the very nice animation of a flowing bag, i decided it was best to do some filming first. Some time last week i set up a tri-pod and a handy cam, and thought it would be good to film it in front of a green screen, so i could have a go at removing the green and seeing how it would look on a 3d background, also it is there so i could easily draw over the top of it. Me and Kiril, still thinks its better animated in drawn 2d, to keep that look that we want.
The animation has been done in Photoshop CS3 using the new video layers, i knew it existed, i just didnt know how to animate on top of it. Once i found out i was thrilled as it has lots of potential. Anyway, this is how the bag animation looks so far. I haven't removed the background layer, so it can show an example of the way the bag is filled in, plain white.