Here’s a better version of the CNC test, done with a small ball end mill so it looks right:
Also, here’s the result of another one of the included G-Code files from EMC2. Superficially it looks pretty neat, but it exposes some of the issues I’m currently contending with, like backlash and proper stepper configuration. The circle is not circular, and none of the dimensions seem quite right.
And lastly, here are more pictures of the conversion process: