Last weekend I spent some time doing this work. My roof was squeaking and it was very annoying.
I didn't had the gummy pflege that all in here recommended, but I did had 303 marine spray that I know has been working nice for all the plastics, so I used.
Cleaned all metal joints and rubber seals, lubed all the metal joints with white lithium grease, and dressed all rubber with 303. Results.... Amazing! I don't hear any squeaks or noise from the roof at all. With the roof close you would think it's a normal coupe. I can't believe the difference. Late on Sunday I finally got the gummi pflege and re dressed all rubber with that just because...
Conclusion 303 will also work. I think the clue it's clean all the rubber and grease all the joints.
Thanks for sharing your tips.
Enjoy!