Piece of advice
You just traced some bitmaps, you'll need a lot of them and know how to use them well or you'll end up looking like a lazy know-nothing animator.
SO use more than just one zombie.
Or instead of tracing bitmaps go copying them on top as they take upl ots of space.
I mean this thing is HUGE in regards to it's lenth.
Or maybe it's due to the avi you inserted att he end...
Well if you work on this it may look good.
WORK HARD MAN