Thank you all for your considerate replies.
I checked the reels: 100% straight.
I re-read the manual, citation: Bend a 120 Film Clamp and place it over the end of the film into the grooves of the reel ... Add a second film clamp on top of the first one. For extra assurance use a 1 in. piece of leader tape to bond the end of the film to the film clamp.
What are these "120 Film Clamps"? - any idea? How prevent that too much chemical is carried over in such a bent clamp? And leader tape on the back of an image?
Any further advice is most welcome!
How do other "rotators" deal with the risk of the film slipping out?
I'll also drop Phototherm/Cytotherm a line: They are in deed caring for their products and customers.
Thank you again for constructive suggestions!
Good light!