Ravelry has saved the day for me. Yesterday I broke out my new KnitPicks ball winder and a hank of Gloss, and I had some difficulties. Fortunately, this Ravelry thread set me straight. I thought I'd share my new knowledge for the rest of the world.
The first troubling thing was the spare part in my hand. I had the whole thing assembled, but I still didn't know what this part was for. However, the Ravelry thread pointed me to this video:
It turns out the spare part is a "handle" you can put on the bottom of the ball winder. I'd rather have it clamped to something, but considering how messy this part of my apartment is, I'll probably need it at some point.
I also, this kept happening. The yarn kept winding around the base. The problem was the position of the metal guide. (Check out where the yarn was hitting the base.)
It turns out the yarn guide moves.
Of course I'd finished winding the yarn before I figured that out.