McNolo
Registered
I tried it and I couldn't get it to happen. You're going between 2017 and 2012? If you have separate files, maybe a material is named incorrectly in 2017?
The initial project comes from Max 2012, but I have been working with Max 2017 for some time now. Those two images that you see, I have exported them with Max 2017 one after the other, just replacing the plugin. So, I don't understand what happend.
Have you tried two different materials with two IDs on the same object?
In any case, I will try to import everything into a new project, maybe it will works.
Edit, it's the same file.