No matter how you build the mesh, the first bone, BIP01, must be some units over the floor, and that floor must be lit. In my Mod, I've had abunch of problems identical to yours, until I make this bone in all of the buildings of the map be in the enlighted part of the map, no matter where the mesh is located, in fact some of them are in areas where no light is applied and because the bip01 is in the lighted zone, the model is lit aswell.
Look at this pics, the first show the same prob you have,look at the turbines on the right of the door; the second show the new models with the Bip01 set on the very center of the map, which is where the main light of the map is applied. I must say that ther's only one central light in the map,ONLY ONE.
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