Regarding speed, I copied the 3 default print qualities in SnapmakerJS to Cura, and generally print Normal or High. I’ve also added two more settings, Ultra-High and Prototype. Ultra-High prints at the same speed as High Quality, but with a 0.05mm layer (the smallest allowed by Snapmaker). Prototype prints a 0.2mm layer, and all of the non-initial-layer speeds set to 80 mm/s. I most use Prototype when I’m designing models, and need to verify that I measured correctly.
Just to double check, did you follow the instructions for setting up Snapmaker in Cura? I don’t know GCode very well, but I think the extra GCode is just to prime the nozzle. So I don’t think it’s strictly required, but should help get a good initial layer down.
I would like to hear your results. I haven’t had any issues switching between SnapmakerJS and Cura, but I have been considering OctoPi.