I am seeing a issue with UCCNC doing sort of a circle, outside of the actual path, when cutting. It happens on arcs as shown circled in the attached png file. The spiral is not part of the path, it is like UCCNC keeps going with the arc into a circle and then picks up where it should afterwards.
I included the milling profile and the g-code (heart.txt) files so you can try to reproduce if necessary. The g-code lines this happens on are around 192, 352 and 541.
If you use lines instead of arcs it correctly follows the path.
Hopefully this is clear as it was a bit hard to describe but it is easy to reproduce using the g-code file, hopefully you will be able see what I am talking about but if not let me know how I can help.
Thanks,
RJS