I am putting the finishing touches to my map, but i have a problem with the cracked concrete texture. I have tried a couple of them but they are acting the same way. They act the same way as the vertex texture, they change lighter to darker.

If you are talking about the tan looking rock and concrete texture with the large black cracks then yes, that is a vertex texture. It was used on certain models in the underground.

So all the cracked concrete textures such as cracked_c, cracked_n, cracked_nw and so on cannot be used because of their light problems.

Haggis, I guess you can make your own versions of these textures but using the LighmappedGeneric shader instead. Let me know if you need a hand on that

That would be great Jose, no rush, when ever you have the time.