I've learned that I have to put both files into a security sandbox, so I added the path to both files (HTML+swf) to a file test.cfg in C:\WINDOWS\system32\Macromed\Flash\FlashPlayerTrust.
But still the same problem. What to do?
Flash + PHP to make a submission form?
Call a method in a WPF app from Flash swf or exe
Adding a node to an xml trace causes no data to appear
Iirc, you can specify always or sameDomain and it will work.
Jquery Make Flash 100% fit to DIV
The second option obviously require the swf to be coming from the same domain..
Using PHP to write to .swf files
Flash AS2 + XML