Hi Charlie - no worries, thanks for the quick response. Here is the log file:
https://gist.github.com/dandelany/8f81a288038d708ffa3f6c7214533d86
Hopefully that's helpful; looks like you were right about it being an OpenGL issue. I'll try to get my PC running soon so I can try PixelCNC natively.
[EDIT: I've just realized I'm running Parallels 14, docs seem to imply Parallels 15 has better OpenGL support. I'll try updating and let you know if it helps...]