@ privateer
I followed your instructions: I prepared manually the mtl file for compatibility with MeshLab, filtered the model in MeshLab and re-exported it using the options you had recommended, I processed the obj file using your obj sorter v2, and last I added the subset names manually (I didn't re-edit the mtl file though).
This time GR2Editor v .374.1 didn't throw any error on importing the sorted object (used the file previously edited by Targor as GR2 template).
I was also surprised to see that now subsets are processed correctly.
Anyway, when I tried saving the file, I got the message that some chains were broken, and GR2E refused to go on with the saving.
I tried then with v 320.1 of TDW's program. This time no broken chain were reported, and yes, the newly generated file was much smaller than the old one
I opened the new file in GR2 E v .374.1, to check that nothing was corrupted, but no, the model was rendered correctly and no error was thrown on opening the file. I was about to report full success but at the last minute I decided having a look in the new file with Goblin, and this is how it looked:
Might it depend on the file that I imported the sorted meshes in, or on some other mistake on my part? Can you replicate my result?
I feel we are just a step from the ultimate solution