Loading library assets from external .swf

Question

Ok, so here's what I want to do. I'm creating an application
that has optional classes that it can instantiate based on what the
needs are. These classes operate things like Session Logging
utilities, etc. These items obviously have assets that they need
available such as movieclips and buttons. For example, the Session
Logger has a sessionLog_mc clip that has a log window with buttons
and the log display. I want to be able to have my class load the
external .swf that contains the assets for the Session Logger and
then use attachMovie(), once the .swf is loaded, to attach the
sessionLog_mc from the library of the loaded external .swf file.
This does NOT seem to work at all. This seems like it has to be
possible. I don't want to be forced to put all my code into
external .swf's too. I just want some external asset .swf's (or
maybe just one large one) that I can load. Is this possible? I am
wanting to have the ability to show the progress of loading each of
these components while the application is starting up and loading
the asset files. Thanks so much!
Here is an example of what I'm trying: (the attachMovie does
NOT work at all)

Answer 1

I see now how to import and display a library class object
using:
var MovieClipClass:Class =
Class(loader.contentLoaderInfo.applicationDomain.getDefinition("myLibraryAsset"))
var movieClip:Sprite = new MovieClipClass();
addChild(movieClip)
But this seems to only work for SWF's published for AS3 Flash
Player 9.
I need to do the same for SWF's published with AS2 Flash
Player 7.
Any ideas?