Then use it. What's the problem? It was intended to USE an actual texture, not to borrow it from floor or tile.
Since custom modifier is nothing but a bunch of primitives, you can literally build your own custom modifier in 3D software.
i cant figure out how to apply textures to an md3 file, it would be nicwe to be able to configure a a model and choose an image texture
Just put a PNG texture in Models folder and name it as as the model.
