Ok,
I've tried everything to make this run faster, but it's still not running
smoothly on weaker computers.

The only thing left I can think of is that I'm using MX. Would using 7 or
even 8 make a big performance difference for me?
I'm animating using x/y coords, and using levels to load images, and 100%
width and height.
Please, any suggestions?

http://www.topshelfgraphics.com/tsbe2.html

Script is simply slow .. there are some improvements to the script
compilation in MX 2004 (no doubt in Flash 8 as well) .. whether it makes a
difference to your code depends on your code and how it is structured and
what work you're doing. Generally you get better improvements by improving
your algorithms and then improving your own code .. improvements due to the
internals of the player are of less significance.
--
Jeckyl