Did manage to get a toolchain working for the plotter using jscut.org. Originally I attempted to use InkScape's built-in Gcode plugin but was unable to operate on the circuit mask because there were too many paths. Eventually I figured out that you can ungroup, flatten and then reconstitute all of the features into a single path, though the order to do that requires some stumbling around. By that point, I was using jscut, an outdated browser utility, which worked decently enough. The main problem was that because I didn't have the proper hardware to assemble the plotter head, the Ultra Fine Point Sharpie was rigidly mounted to the toolhead, making it blunt rather quickly, which caused both attempts at tracing the circuit to be unusable. At some point I will retry this with a different mechanical setup because the difficult part, getting the software to work, is behind me.