RTEncoderPy 1.0 is a standalone program (a script thats been turn into an executable) and is available for Windows and Macs (there's a new note on the download page that the OS X Intel download doesn't work with Snow Leopard).
So long as you only make files in V1.0 format, then AFAIK, people should be able to decode with anything that's currently available.

I just wish I could find the format description/documentation I had.