In my opinion it is very likely that door stroke is not set properly. I see this all the time, stroke not set right, guys try to use electronic adjustments to compensate. It may work okay for a while, then a few years down the road it’s necessary to tweak parameters. If door stroke is mechanically set right you can damn near use default parameters. Hard to explain step by step to get it perfect, but TKE or Dover manual for any vintage HD operator will explain stroke adjustment.

The other possibility is that belts were never loosened when operator was new. What I mean is the factory sent out all HD operators, the belts are always WAY to tight. They need to be as loose as possible to barely keep traction on reversal. Knowing this sometimes people incorrectly increase torque settings to compensate for tight belts. Then belts loosen/stretch, or idler arm bearings starts to go out also loosening belts and now you got slamming doors.

As far as pick up rollers slipping out of clutch, score a cross hatch pattern/ or vertical lines in the face of the clutch closing vane with pocket knife . This is maintenance thing I do. Hold closing hall door being careful not to break the beam, if hall door slips out of clutch, start gouging the face of the closing vane.