If there's nobody on that I'd like to know what you think about including the doc into the header and use a doc-tool - e.g. doc++

• to generate printable and html docu.

If I get no response, I'll assume there's no interest in documentation at all and skip this project.

I think it would be a great idea. I have been trying to get a GRX documentation for a long time but I never found a good one on the web.