I use the basic setting in the Snapmaker orca for the PETG I am using. The only other thing is use is vision miner for a bed adhesive / release agent for the textured PEI bed that came with the U1. This is not needed, but I use Bambu Lab high flow PETG which can over bond to the build plate.
I have not had the bed default to 0c for temp as described above, but have been printing since the beginning of January.
So for the settings, Generic PETG-HF for the filament, 0.20 standard and 0.12 High Quality for layer height.