Thanks for the suggestions Willf. I've created an animated ribbon blowing in wind and this is what i'm attempting to render. I did a straight rectangle in the spline modeler and used the wave modifier to do the animation. Now that you mention it, i did have success in rendering a sphere as sequential photoshop 2.5 w mask G-buffer turned on, and it composited just fine in After Effects. I dont know why it is not working with the ribbon though. I will try it with different objects.