Hi Pluto,
There are no built-in single-line fonts in PixelCNC (aka "Hershey" fonts). However, you can use fonts you have installed in combination with the Medial-Axis Carving operation to get virtually the same effect. For instance here is the font "Aristotelica Small Caps Regular":
Here is the resulting simulated v-carving, using a V-bit cutter and the Medial-Axis Carving operation:
Does that accomplish what you're hoping to do?
Alternatively, I believe Inkscape has Hershey text which you can then export as an SVG/DXF and create a paths-layer from in PixelCNC, which can then be used as input to the Paths Carving operation, which will directly traverse the paths from the Hershey text vector.
Hope that helps. Have a good day! :]
- Charlie