thanks for your patience, I was afk due to illness.
Its a bit hard to explain, but to get this material working you’d need red vertex color for any floor related surfaces on your mesh.
You’d need uv-channel 0 for your lightmap layout.
Uv channel 1 for regular uv-mapping (no vertex color (not white but black)
UV channel 2 for hiding seams + green vertex channel.
that way the right textures show up on the right places.