So, I was trying to make the eye of my squid more 3D. I tried to recess it to form an eye socket, but it was deforming the sides in such a way as suggesting a nose or something. So, I decided I would try to make the eye as a separate mesh group and simply add it as a subset. It's been years since I've added a subset to an object and it certainly shows! Even following the tutorial again, I've borked the ever-living bork out of it.

Not only does the other subset not show up, I seem to have also borked the TXMT. I was trying to reduce the shine of the squid. Now, the entire squid has the texture of the eye (the other subset). I need to remesh and remap the eye, but I want to at least get this problem resolved first. I can't see what's wrong. I'm at the point where the more I try to correct it, the worse it seems to get.

That is an ... odd statue. No idea of it's purpose. But I do understand all too well things getting worse when trying to fix them. Fixed the subsets, both are recolorable. However, it can't be recolored or selected once in game. I suspect the bounding box is off, quite possible because you imported the shadow mesh by itself? I did not fix that since you said you need to remap your mesh, which should correct that issue when you import it again.

The subsets were not listed in any of the required places, so I added them to the GMND, SHPE, MMAT, and linked them.

Yes, it's quite odd even within its context. Thanks so much for fixing it for me! (It turns out you can grab the squid's eye, but for my purposes it's already in position. I don't think anyone will be using it outside its context anyway. )