This repo contains examples of Postscript programs that generate Supernote templates.
If you have an idea for a template that you'd like to implement in Postscript, reach out to me and I'll try and help you with that. This is a weird thing to say, but I wrote Postscript professionally for almost ten years way back in the 90's. It's an esoteric skill and while I don't think I could get a job doing it now, I have a lot of years on it and I wouldn't mind a reason to refresh.
To generate these templates you need Ghostscript and make.
Make all the templates:
$ make all
Make one template:
$ make templates/5mm_dotgrid.png