I need someone please be so kind if you get on this topic coreshaders content of rfactor 2, since I can not remove it with MAS2 (unknown mas key). Without the content of coreshaders I can not do anything with 3d studio max, it makes me shaders failure.
Delete every rF1 shader from your HWShaders folder and put your rF2 coreshaders.mas into it. There are some shader errors when you try to import rF2 gmts, but that's because there isn't a new importer, only the rF1 ones.