The key to smooth operation with your cover is to ensure that the rails are level and aligned correctly. The following will review what to check with your rails to ensure they are level and properly aligned. You may also find this article helpful: My cover does not operate well. What do I need to adjust so that it operates smoothly?
Quick Clamps
If you have quick clamps you will want to view the following video for alignment:
To check your rails to see if they are level, reference the following article: What to do About Rough Operation
Bolt On Brackets
If you have bolt on brackets you will want to view the following video for alignment:
To check to see if your rails are level, reference the following article: Checking for Level Rails (Models not using Quick Clamps)