Sunroof Problems

[flying_violin]

I recently bought a 1991 318is, and have fixed all of the major stuff so that now it runs quite well. However, I am now trying to fix the non critical things on the car! Next on my list of things to make better is the manual crank sunroof. The previous owner told me that the sunroof was opened once, and then they had to get a mechanic to close it. So (naturally) I told myself, "What's the worst that could happen?" and went for it. The handle turns freely, and I can see something moving inside after I removed the black trim piece. Once in a while it feels like something tries to catch but then it frees up again and turns with very little effort. I opened up the Bently to see if I could take something apart to get at the mechanism, but to repair the sunroof it says that the first step is to open the sunroof. So it sounds like I need to fix my sunroof so that I can open it to fix it... What could be going wrong here?

I tried searching this topic already, but couldn't find much.

Thanks!