Global Mapper v24.1

Output as a map tile (WMTS) for geoviews

This is probably beaten to death and my amateur search couldn't find it - so thanks for your patience, here goes:

I am plotting fairly extensive trajectory data in a python application using Datashader and it looks like I have to use a holoviews/geoviews map tile or similar product so the layers all work. I can do that, but I would rather use a custom version that I have modified in Global Mapper with a terrain legend that makes more sense for our application and custom feature layers.

I can see that GM imports WMTS but doesn't export it. There is a WMTS converter in geoviews. My guess is there is a trivial workaround with a compatible export format. I'd appreciate any pointers toward that format.