When loading a model with meshes that share one same material (material settings and textures), make sure that you split them into different materials to adjust the settings. For this you may use the provided Make Unique feature.
If several meshes are assigned with the same material, then once you modify the material (texture and material settings), all the meshes will be affected.
Use the Pick tool to click on meshes and find out if they are using the same material ID (identical name in the Select Material list)
Modify the texture or material settings of the material ID.
The other meshes are all affected
Glow map applied
Use the Pick tool to select the mesh you wish to individually separate material.
Click the Make Unique button in the Material section. The material of the mesh is then isolated and renamed with a suffix Copy added.
You may then modify the content of this new material without affecting any other material.