For the AO MTL files I can't just place one material entry in them. This is because each subset can have a different material and thus there would be different entries. I'm thinking it over as to how I want to remedy the duplicate entries though.
The 'd' parameter and 'map_bump' and 'bump' entries have been removed from the AO MTL file.
I played around with the material bindings to ensure the app wasn't causing an error in the file. App is writing files fine. The problem is it appears Goblin and the game will only allow x material bindings for x mesh subsets. i.e.: if the mesh has 5 subsets then you HAVE to define 5 material bindings for the mesh. Anything more or less and Goblin and the game will crash. This is the devs not understanding the Granny format it appears. Granny Viewer will load GR2 files with more or less material bindings than subsets with no problems. Not much I can do about that - those are the rules defined by Goblin and the game
@BIGREG - the error you are getting when you rename a mesh I can't reproduce. I'll need to see the GR2 file and tell me what you did so I can try and recreate the problem to see why it's throwing an error.