Hi, did you ever get the system working correctly?
I also experience the same problem with a new Rolock 90 on a new Nova from Seaskin that arrived in December.
Lubricated, and stored cuff twisted on between dives. Twisting off still requires me to wrap both sides in rubber. Prior to dives, it requires a second pair of hands to attach and is extremely difficult to twist off with help.
I believe something is wrong with the cuff o-rings out of the box. It took two people with the cuffs wrapped in rubber to separate the rings out of the box for both cuffs. The o-rings were dry. Lubrication helped a little, but not much.
I have cleaned these, removed excess lube, applied lube.
I believe the o-rings are defective and need to be replaced.
These are not working as a removable system. I wrote the Rolock and Seaskin and will see what they say. Not hard to send new o-rings.
Cheers