Can you overlap maps in non-lightmap uv channels?

I’m really wondering if I can overlap maps in uv channels that are not being used for lightmaps? I want/need to be able to overlap maps like the diffuse, and normal maps etc.

Also, I have one more question: When I am unwrapping the light map channels and I have two different props where one has more surface space than the other. Do both of those prop’s lightmap uv channels need to be scaled the same? Like what if one prop is 100x bigger than another. When I unwrap the lightmap uv channel of the smaller one will it need to be scaled really small?

Yes, non-lightmap UV’s can overlap, it doesnt cause any issues.

Regarding UV space, if those props are sharing the same UV space(like merged meshes) then you should scale them depending on their size. Otherwise every mesh should use as much UV space as possible; then you can adjust the lightmap res. depending on the mesh’s size.

Thank you very much.