Don't forget to adjust the ambience value in MED for your model before saving it to MDL, otherwise it appears black or super bright in the game. I find a standard ambience in the "material" section:

Diffuse = 50%
Ambient = 5%
Emissive = 5%

Try that, see how the model looks, you can always reload your model into MED, change the values and resave. To give it a texture, just go to view skins and import a bitmap. I hope this helps.