Full Complement

It's took me some time, but I became serious tonight about figuring out how to import a SWC file into Flash CS4 and I'm glad I took the time. I found this extremely useful video demonstrating how it works.  In a nutshell, you create a class in Flex and it is packaged simply into a single file called a SWC. This file includes the class code for easy importing into Flash.
From your Flash CS4 FLA file, you can add a SWC file from the Publish Settings page. Basically, you now have access to this class in your ActionScript code with a simple import (no need for all the AS files). It finally allowed me to import two useful libraries: AS3Core and XMLSyndication. I then could create a simple Flash RSS Reader using Mike Chamber's blog entry for parsing feeds.