This makes many things clearer, and explains why you've been encountering these problems.
You're using a workflow for the Genesis 8 Female figures, which is not supported anymore by us. To be frank - we've stopped supporting this workflow with the original MK3 shaders for Genesis 3 Females, since it is way less convenient than the method we're currently using.
Loading the .duf-file to work with the shaders, is not required anymore. You can simply start with a plain and empty scene.
Most importantly:We've introduced 2-click-presets with RedSpec TGX tailored MK3 for Genesis 3 Females. These are
MUCH easier to apply to a figure, as it is all done within 4 mouse-clicks and you don't need to manually drag-and drop materials anymore.
Applying these, is explained in full in this brief video tutorial here:
https://vimeo.com/196940156 (the video is for the Genesis 3 Female shader but it works just the same for the Genesis 8 Females).
Please use these, as I've mentioned above, the "old" dragging and dropping isn't supported anymore. The file you're trying to use is not meant to work with Genesis 8 Females, plus, it was created with a much older version of the OctaneRender for DAZ Studio plug-in and it would surprise me, if it would still work at all at this point, since there have been many updates to the plug-in since.
Sorry, for the inconvenience this created for you thus far...
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