Measurements:
 - change Solvespace so that DXF import automatically adds constraints
   on lines that share points (exactly same)
 - adjust the other dimensions according to SVG/DXF measurements,
   see uncommitted files here in pcb-outlines/

Adjustments:
 - on the right part make sure the stubs have space around when viewed
   from the bottom, like with the left part
 - make the top and bottom tolerances a bit bigger (try 0.05, 0.10 on each side)
 - the far edge should be about 1 cm taller, otherwise pressing the bottom
   row with MBK keycaps isn't very pleasant

Making a better, beefier version:
 - the cover has no chance of working well with such a small base, it needs
   to lie straight on the PCB, and the whole assembly needs to wrap the PCB
   including the sides, otherwise it doesn't work, nor does it look good
 - underlighting has turned out to be too non-uniform, even when using
   a slightly diffusive translucent material; jet black would look better,
   maybe with some small squints/grooves or holes to prevent the LEDs from
   drawing power undetected
