for your own skin dds files, it's better to have their own file names
{"pilot helmet",DIFFUSE,"own_file_name", false};
{"pilot helmet",ROUGHNESS_METALLIC,"own_file_name", false};
{"pilot helmet",NORMAL_MAP,"own_file_name", false};
{"pilot",DIFFUSE,"own_file_name", false};
for modelviewer, there's config file for you to add texture folder path