ok so you went to nVidea and downloaded and installed the vMaterials and the MDL Exchange correct?

https://developer.nvidia.com/vmaterials

AFTER installing that. you need to move the nvidea vMaterials to your core DazStudio installation should be under Program Files a shown above in the pictures. AND also as shown above use Daz Studio to point the MDL Directory Manager to the MDL Exchange path: C:\ProgramDataNVIDIA Corporation (This may not be necessary but I did it just in case)

DAZ Studio has to be able to locate the MDL files for the Shaders to work. Since I am suggesting to move the entire vMaterials folder to a location where the MDL files already are located I am assuming this is a built in directory. IF DazStudio cannot access the MDL, it cant interpret it.

The Shaders in the ZIP file are installed into your DAZ 3d Library. The shaders act as a go between between the MDL files and DAZStudio. Basically each MDL is a BRICK in the shader editor.

SO when you say you installed the vMaterials textures to: ...DS4ContentnVidiavmaterialsaectextures. Is that where you placed nVidea's vMaterials folder? If so that's the problem. Their folder contains more than just textures, it also contains mdl files (which are basically txt files) that tell iRay how to function. DazStudio isn't looking there for the mdl, its looking where I suggested you place it.

aka MCDLabs
also known as Daniel Merrill a grumpy old disabled Jarhead.
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