Loading external fonts in AS3 projects can be really complicated, and there is not a lot of documentation online, except for a few blog posts for Flex.
This article explains in detail how to proceed to load external font files contained in precompiled swf files. The author even provides a FontManager class to easily manage the font registration once it’s loaded.
http://www.betriebsraum.de/blog/2007/06/22/runtime-font-loading-with-as3-flash-cs3-not-flex/
