My H2D has produced good single layer prints with both nozzles and PLA. The front lower bed screw was already backed off enough. The HF PETG required a slight Z-offset adjustment, which I added to the filament’s start G-code.
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This was with the smooth PEI plate.
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If you notice small PETG ripples or waves, with the stock settings you need to adjust the Z-offset with this code.
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I always use a 0.24 mm initial layer height for all of my PETG filaments.
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G29.1 Z0.05 ; To adjust the nozzle Z gap fine-tuning in increments of 0.01, either up or down
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Mine turned out perfectly with a 0.05
It would be wonderful if Bambu Lab could add a z-offset option for bed plates in the filament tab. 
Note: Edits reflect only the updated text to ensure clarity for users