Screen Retractable Projector

Retractable projector screen problem?

I have a roll-up projector screen that you pull down and it is supposed to go up. It is mounted to the ceiling and pulls down, anyways I was playing a video game and got mad and I threw a pillow at it (don't ask) well it rolled all the way up very fast, since then it will only go up part of the way it is impossible to get it to go up all the way. Is there anyway to fix this, my guess is there is something broken but I have no idea what it is. Thanks in advance for the answers. I am also open to redneck/jimmy rigged ideas.

Take the end piece off of the screen with it rolled up. You should see a spring coil on the end. Tighten the coil a few extra rounds and it should be able to close the screen all the way.

Yahsin Projector and digital pen concept at Cebit 2007