crossdomain.xml - это про securityDomain, а вам, видимо, нужен applicationDomain.
Цитата:
|
When loading the file, you can specify that the file be included in the same application domain as that of the Loader object, by setting the applicationDomain parameter to flash.system.ApplicationDomain.currentDomain. By putting the loaded SWF file in the same application domain, you can access its classes directly. This can be useful if you are loading a SWF file that contains embedded media, which you can access via their associated class names.
|

Код AS3:
var context:LoaderContext = new LoaderContext();
context.securityDomain = SecurityDomain.currentDomain;
context.applicationDomain = ApplicationDomain.currentDomain;
var urlReq:URLRequest = new URLRequest("http://www.[your_domain_here].com/library.swf");
var ldr:Loader = new Loader();
ldr.load(urlReq, context);
http://help.adobe.com/en_US/as3/dev/...0204-7e13.html