[TheDarkWraith]

Originally Posted by gap

So, open the GR2 file contained in this package, right click on the first unused material (i.e. standard_13) and select 'delete'. Even after being deleted, it will keep being listed among the other materials. You will know that it is actually an empty name because, if you try deleting it again, you will get the message:

"Can't delete material because it doesn't exist!"

Save the file now. Everything is apparently fine, and the deleted material will be removed from the list of available materials, but if you try deleting the next unused material (material #985), you will get a "Collection was modified; enumeration operation may not execute" exception, and the file will close automatically due to corrupt memory

Files or memory getting corrupt while deleting materials is a very common error, and it dates back to v 1.1.374.1 (or even older), even though I don't remember if in the past it showed the same way as it is now.

Sounds like an easy fix. Looking into it now