Hey Furdle.
I've got a little information about the mod, it gives you the ability to flip (like if you fell on your ski's and your player would flip around, but in your control.) It also gives you the capability to climb, and a little extra speed. That's what I've seen at least from the beta testing. As said in the OP, it's private, and I really don't have any more information about when it will be released and that type of thing.