Files Associated With Material Appearances
You can define appearances for a material using the Appearance tab in the Material Definition dialog box. The names of the material appearances that are associated with a material are stored in the material definition file, that is, the file with a .mtl extension. Information about material appearances is stored in the global.dmt file. The default location of the global.dmt file is \<loadpoint>\graphic-library\appearances. However, you can set the global_appearance_file configuration option to a path that points to a different global.dmt file. This file takes precedence over the global.dmt file in the default location.
The global.dmt file is different from the appearance.dmt file that stores the information of the appearances created using the Appearance Editor that opens when you click View > Color and Appearance.
When transferring a model you must transfer the associated global.dmt file along with the model. The appearances information other than default is not available for all the materials saved with the model if the global.dmt file is missing.