Yeah something is fucky in this release of BBUslicer, it usually opens my file, but will sometimes crash once or twice first. Unfortunately, Bambu P1S so no Orca for me (EndeavourOS / Arch derivative)

When i ordered the p1p to p1s conversion kit for mine it appeared to be hung up in CA forever according to UPS, but one day it was just there. Not sure if its just something flaky with that distribution center or what.

All your design work would be outside their software (Fusion, Solidworks, Tinkercad, etc). You would then export to a 3mf (native) or stl and then import that into the slicer program (this is where the “walled garden” starts). That translates it to gcode that the printer then uses, almost like a backwards CNC.

Other things to note regarding filament- if youre only planning on making items for indoor use, PLA / PETG will be fine. If youre planning on using things outdoors or in hot temps, you’ll want to look into more advanced filaments like ABS/ASA, Nylon, etc. These absolutely require an enclosed printer, whether thats part of the design or something you put over top of it to keep the temp inside higher. I’d highly recommend figuring out your ultimate use case and make a decision around that.