This article at sitepoint explains a good practice for structuring a Macromedia Adobe flash file. An interesting read for those who develop in flash :The Best Structure for a Flash Site

to summarize:

Frame 1: set up global variables
Frame 2: load XML
Frame 3: load CSS
Frame 4: build the interface.

the idea is to keep everything that could be updated external of the flash file, in an xml file or in external jpeg, gif, png, videos, etc…