How about Actionscript 2? Flash basically has two VMs . . . one is used to run legacy content (up to Flash 8, AS2), the other for newer content (Flash 9+, AS3).
But my reading of the project page suggested it was just converting graphical and animation elements in .FLA files.
I have tried different .fla and if there is a line of actionscript (even if not used) the conversion fails.