Antwort auf:

---

bmap box = <box1.tga>;

material spec_bump_model //assaign all models this material in script
{
skin2 = box;
flags = tangent;
}

---

gives you problems because this way, you assign a second skin to the material, not the model that uses the material. As far as I'm concerned, the shader needs the model to have the skin, not the material. Thus this is what you do, basically:
1. - Open your Model
2. - Open the skin editor
3. - Import you basic model skin (has to be TGA with alpha)
4. - Add a new skin (Edit -> Add new skin just in case this is confusing...)
5. - Click Next Skin and import your normalmap
6. - Save and have a try

Hope that helps!