Hmm... I'm thinking it could be a defect in your track. Try this: remove your operator from the window and then open and close the window manually. If it operates freely then it's the operator causing problems. If it still binds, check the track and hinge for any kind of obstruction. Maybe even a screw that is sticking out too far.
The window does NOT bind, I can pull the window shut and have to push it open for the 1st inch of travel. Then the gears engage.
I am trying to find a replacement operator.