How To Make A Movie Clip Run Backwards

Here's an example
There's only one tween in this movie

1. Create a new movie clip (Ctrl+F8). (In this example it is "ball MC")
2. In your movie clip's editing mode, create a grapic symbol (in this example it is the "ball"), add some frames and make a motion tween.
3. Add a new layer and name it "Actions", add a new keyframe (F6) in the last frame and put the "stop()" action in both keyframes.
4. Create a new movie clip (Ctrl+F8). (In this example it is "back MC")