1. I'm not sure how you make an image auto feel a matte. What tutorial are you talking about? Can you just resize the image so it fits?
2. For the second question you need to place that 2D background layer in its own group that is not in the 3D group. Then make the 2D background group 2D. Then the background will not move with the camera move.
Hope this helps and best of luck.
Stephen Smith
Utah Video Productions
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