In reviewing a portion of the Supercam online documentation, I have to wonder about the algorithm that they use for arcs: specifying a start angle and an end angle as vital arc parameters does not parallel the method used in a typical controller. Thus I am still suspicious of the mathematics used to convert those angles into a G02 or G03 movement.

Have you tried contacting Supercam support?

http://www.super-tech.com/root/supercam/default.asp