Looks like its a start but has a lnog way to go.
If you're going to do stick animations, try to make it a little more fluid, pan the view back a little because all the shaking and jolting of the background make it very hard to tell whats going on.
Add more detail to the background, and more details in general, work on the explosion effects, maybe look up a few tutorials. It's a good start, and it looks like you've got a decent grasp on how flash works. Now all you really need to do is put some more time into the characters and polish up the bits that are choppy or where the character's body positions are a bit ambiguous.
Also, put a stop event at the end of the layer with the music on it, that way it wont loop after the movie ends, throwing off the synching with the movie if they decide to play the movie again.
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