@WillAdams thanks for the heads up - I’ll check it out.
@neilferreri “Arc Endpoint Error” which there are many cases of here on the forum. Also the radius form of the arc command comes back as “unsupported”, which I’m pretty sure isn’t correct. (Although I’m not sure of course - I like the idea of sending it to the GRBL controller in debug mode; I didn’t know about that.)