There are many questions, about using Flash 9 swfs (AS3) with existing version of SWF Studio. As Northcode is going to release AS3 compatiable Studio (somwhere) in 2008, till then the best way to do is to use a local connection method. I have used it in many projects successfully (still I believe it is not clean !). To use local connection, create a command list in a Flash 8 swf and connect it via Local connection from an AS3 based SWF . That’s easy and works great .