I believe I could have some help in mind. Put the material in mmmaterials.brf not mm_french_hats.brf and any new textures into mmtextures.brf likewise, I am not exactly sure why but it seems this fixes a lot of problems for any errors on models for NW.
It appears the envmap appears fine for the mesh's .1 attachment so try the above changes.
It is refreshing to see more people try their hand at modding the game, keep at it and it will pay off in the end.