Also note that the crowd receives the below mesh lightmap as a shadow, so try to tweak that too
Here is what is happening with the black hairs:
From version 0.63 and forth all data is being passed back in the head and hair files, and that includes both uv maps and both color maps. Now that color map rewriting maybe when you have tweaked the hair in a large percent will have that kind of impact in the appearance of the hair in the file.
It has nothing to do with the textures, it has to do with the light that the hair receives and that is a color map issue.
I thought that i had included the possibility to overwrite the model without containing the color maps, but i was wrong, just checked it and the file gets an error. So either use the previous version for now, either try the autopainters included to recolor the meshes ( i absolutely don't guarantee the success :P:P) either wait for the new version in which i'll try to fix that