Smooth Arc Function

Last year I bought a 3-axis DRO to go with a new BP clone, and I was excited to find out about the smooth arc function, however I cannot get it to work. I assume there are parameters I do not understand, but I'm a smart guy and I am at a loss. For reference, it is a DRO Pros 3M, Z on the knee (I also have an independent quill scale).

For reference, I have the origin set to the rear left corner of the work. The flycutter has a 73mm cutter radius.

I want to cut a convex 329mm radius arc...

Smooth Arc Function