I suspect the key unscrews backwards, the hand adjuster pulls out (like an old alarm clock), and the other thing... 'aint got a clue, keep poking and prodding it to see if you can figure it out.
EDIT: ".. the other thing.." is presumably the regulator, and I suspect it has a two pronged fork on it that sits over the internal regulator arm, so it may not need much poking and prodding, it may simply slide off.
I'm not sure about that now. I will need to check it out when I go over his house. I was sure the main spring was oiled to much and it was slipping. But since you can wind it and it works fine. It has me puzzled. Maybe he replaced the main spring with a stronger strength spring.