what most of use would like to do is using tools like 3dsmax, maya, modo,... they are no game specific light mappers. their automatic uv-unwrapping algorithms most likely are quite generic and not optimized for this purpose (but their advanced renderers are great for baking lighting into textures). with all the freedoms these tools allow in texturing, i think for doing a robust importer you better shouldn't expect the uvs coming out of there to behave in a certain way.

maybe you could post a screenshot of how the 3dgs light mapper packs uvs?

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i don't know yet when/if i would try to do such a light map importer.
- i currently don't have much time
- i would have to do some reading about these d3d buffers
- the %$"§$% visual c++ express doesn't come with win32 support out of the box
- downloading the needed huge sdks is stupid with my monthly bandwith limit

...but thanks for your offer to help!

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would it be a lot of work for you to change c_trace so that it also could return the brightness of imported model light maps? in case we use model light maps it of course also would be nice if entities could react to them.