Creating a Flash movie in PHP involves first getting over the fairly steep learning curve. When you are getting started, figuring out all the classes, objects, animation, and jargon will take a good amount of time and effort on your behalf, but I believe you will find it pays off - you can really get some cool results with Flash, and even more so when combined with PHP.
I strongly suggest you write your own functions to handle as much of the repetitive code as is possible - once you get the boring stuff down to one function call, it becomes much easier (and more fun!) to write Flash code.
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