Probably, the easiest way would be to have all of the potential backgrounds as frames in a movie clip behind the avatar area, so then you could use a gotoAndStop(x) with x being the background you want.

What version of flash are you using?

I tried both that and the square brackets version. Also, my flash player runs the admin panel no problem(using flash player 8 ).

For some reason, I can connect to the server I'm using when I test an application in flash, and the admin.swf for the server connects just fine.
When I telnet the ip and port of the server, I get:
<cross-domain-policy><allow-access-from domain='*' to-ports='9339' /></cross-domain-policy>

However ...