Try increasing hotend temp for first few layers and hotbed temp throughout

the default from the printer was 60C. I had some better results with 70C. But the issue still happend with more delicate prints.

those PEI sheets usually need higher bed temp than the regular sheets

thanks. I didn’t know that. What magnitude are we talking here (like: 10K more for PEI-sheets? or more like 1K?)

Try moving z closer for first layer

I think this may be the solution. How much should I change the z-offset? (the print in the video has 0.2mm layer height. And the worst-adhession issues happened with 0.1mm)