can I add a new twxture to a model using text editing the mdl file?

[Percivali]

Can I? and If the answer is yes, how?

 

[PurgeandFire]

You can, but it depends on how you want to do it. If you want to replace a texture, then it is easy. Simply go to the block where it says:

Textures <number of textures> {
        Bitmap {
                Image "some-image-path-here.blp"
                <other stuff>
        }
}

You would change the path to the name of your texture. When you import the model, be sure to import the skin under that same name (the model will look-up the texture under that name when it is being loaded by the engine). However, this can be done more easily through MDX Pather:
http://www.hiveworkshop.com/forums/tools-560/mdx-pather-62978/

If you want to add a texture, then editing it through the MDL is a pain. You would have to increase the texture count in the texture block by 1, add it as a separate texture, and then update materials to use your texture (by inputting its texture ID). Note that you must follow the format correctly or else it wc3 will fail to load your model.

Instead, you should use Magos' Model Editor (found in our tools section). Just go to Windows -> Texture Manager, add your texture name. Then go to Windows -> Materials, click on materials and change the texture to use your texture. If it appears black, make sure your texture is in the same directory as your model and that it matches up with the "path" you input into the texture manager. If it looks ugly, then you made need to change the UVWrap of the model.