I love my Patterson. I do 35 and 120 and have never had a blown roll.

2 suggestions:
1) Load a test roll in daylight. Sure it is a waste but seeing the magic might help
2) I have never used a bag. When I am in complete darkness my sense of feel is amplified by the loss of sight. That extra feel I believe to be the determing factor.

Sorry to hear of your results thus far. When I learned darkroom in class my teacher insisted upon proficiency of #1 above before even trying #2 above