This exact thing happened to me with my hilt. I had played with materials in blender to see kind of a ‘draft’ of what the finished product would look like with materials not realizing it would create some ID confusion in instaMAT (hilt appeared all speckled when trying to mask via mesh id). Removing the materials in blender, re-exporting my FBX files, and re-baking in instaMAT completely resolved it. Next time I want to have some materials playground time I’ll be creating a new collection and duplicating the model into that collection to keep it separate from the model that’s intended for export.
