Hoisting main sails...
There is a good FAQ on sail hoisting:
http://www.hobiecat.com/community/viewtopic.php?t=371
From the FAQ, here is my best guess on the issue at hand...
The best way to feed the sail is to stand in front of the mast and reach around either side to "sandwich" the sail between two hands (above the feeder opening) and push the sail up the track. Pull with the halyard, only the slack created, then feed again. If the sail binds, lower slightly and begin feeding again. This technique can be done by one person, but is certainly easier with two working together. It is VERY important that the person on the halyard only pulls the slack up the mast and does not get ahead of the feeder.