That again sounds a lot like GMax. Discreet has gone so far as to warn against trying to write conversion plug-ins for their '.gmax' format unless you get a game pack development license from them. The big problem they'll have (are already having IMHO) is an end user can almost always use a game pack formatted output as an intermediate for importing the result back into mainstream modelers. I don't know how they're going slow down people 'working around' the format issue so trivially.