Old-fashioned swf loading bar in Flash Player 9? (Can't use external content!)

Hey. I’m making a AS 3.0 game. I’m making it a self-contained SWF so it’ll be compatible with NewGrounds’s flash portal. How do I create a pre-loader for it? I’m pretty sure I can’t use the Loader class, because Loader requires a URL, which implies that the content it’s loading must be external to the swf. (Not, for example, Library content.) My game is a 4mb SWF, so a pre-loader is a must. I just can’t figure out how to do it, and all the documentation I can find seems assume that my content is all external SWFs and JPEGs residing on a web server or something. How am I supposed to make this work?

I found more information on this problem:
http://www.senocular.com/flash/tutorials/faq/

To summarize with AS3 the entire library of a SWF file will be downloaded before any other action is taken. To fix this you can tell each library item not to load in frame 1, and then setup your preloader in the first frame.

I myself am using a separate SWF file to do be a preloader which will in turn load my much larger SWF with a game.

I hope this information helps anyone else who runs across this problem.