Super fun to play with D20. The original model didn't print right for me (numbers hovered over the model) so I fixed it! Print the "spin_dice_alternate_layout_fixed - separate" model to make sure the arrow lines up correctly. 3MF files are just upgraded STL's, interchangeable. They'll work on any slicer. I recommend remixing to add other dice: all the D's, (6, 4...), all 1's except a single 20, unfair dice, etc.

Remixing isn't working on thingiverse again, so here's a direct link to the original model.

If you use PETG, a bit of lithium grease can help. Don't put SuperLube grease: always makes the plastic stick.

If you can't make the gears spin, use Horizontal Expansion in cura. Other slicers have similar settings that might be under different names. You may need to pop each gear loose by pushing top and bottom.