Ok this is pissing me off! I've been getting slammed with the Error #2148: SWF file ... cannot access local resource myXml.xml. Only local-with-filesystem and trusted local SWF files may access local resources. The "common" answer to this issue is to use the compiler option -use-network=false. Sure this compiler option will remove the error, however, you then have NO ACCESS TO YOUR WEBSERVICES that actually NEED connectivity. If you have a basic Flex file and ONLY need local xml, then this will work fine. It seems shitty to me that its an "either one OR the other scenario" ESPECIALLY when almost EVERY tutorial, or blog post on using HTTPService uses a local description (ie url="assets/myXml.xml") or a fully qualified path (which we may not even know until we deliver our projects).
Ya, ok, there is some smart-ass out there that will say, "well if you are using web services ANYWAY, why not just put your .xml in as a web method." Well, Mr.(or Mrs. ) Smartass... I SHOULDN'T HAVE TO. As sweet as Flex / Flash is, you would think that at some point, someone would realize that there are VALID reasons where you might want to keep small pieces of xml in a local file for ease of modification and use.
Oh, and the same error occurs for the URLLoader as well. grrrrr...