The infill should be set to 15% and all the parts should be put to minimize the supports needed. If you want to reproduce the printing you can use the gcode ready to print located in the gcode folder. The gcode is sliced for a Creality K1Max with a 0.4mm nozzle.
All meshes are located in the meshes folder. You can find more detailed instructions on how to print each part in the documentation.
See printing_parts.
For your convenience, we provide the gcode files we used to print the parts.
See gcode_list.