Here is a thread that has the control law diagrams.
Edit:
Always looking for testers. Anytime a new beta release comes out for ArduCopter, it’s always great to have people like yourself, put some time on it and see if there are any issues. Just looking to see if the code retained the same functionality is all that is needed. I don’t believe we have many users on the heli side that do much beta testing. If you are interested in getting into coding, that would be great too. We also invite users to beef up our wiki with new pages or updated information. It is pretty easy to do and explained in the wiki. This is also a hobby of mine that I do in my spare time. That’s why its taken 1.5 years to get the heli autotune to a point where it is ready to be merged. of course, it will be a few more months until it gets thoroughly reviewed by the senior devs and I incorporate there changes.
Glad I was able to lend a hand.