I was asked to find a way for separating our localization resources out of the application swf, so that different locales can be loaded at runtime.
Pretty quickly I found the "Using resource modules" help subject, which explains how to create, compile and load resource modules,  which are SWF files, separated from your application SWF, that contain resources bundles for a single locale.
While trying to set up a demo application (didn't found one) using the instructions in the help files, I bumped into several issues which I will explain here in hopes that it will save you the time, and added the sample app as well.