Hi Nick,

thanks for the motivation reg. "producing  a supplement".

In fact I thought about this quite often, but whenever I start to document such details

I feel very unsure about the format and the needed simplification.

I agree that the availabledocumentation (including wiki and other sources) is behind

the current knowledge represented by the code in mkgmap.

On the other hand, I do like to answer specific questions, because I can expect that the

reader really wants to know the details.

So, I don't see myself as an author, but I'd be happy to deliver answers.

Gerd