Face Gen Problem that's been driving me insane!
I only have this problem with current Face Gen models I've made. It only happens to female models. Everytime I load them up it says I'm missing d6 ext. Files. When I skip them or load the face file it comes up super glossy and ugly. I've made two models I really like, but they just have unsettling faces when rendered.

Comments
It sounds like you are using after you make the FaceGen morph a product called 'Brow Remover'. Then you save your scene & when you exit DAZ and open the scene again those Brow Remover files are gone.
What you have to do, is after you create your Brow Remover 'face texture set' for to Surfaces for each of the Face, Eye Sockets, Ears, and Lips and for each of the surfaces settings for those surfacesthat use a texture or other image map, use the DS 'Browse File...' to find out the location of the Brow Remover texture & you the Windows Explorer or the Apple File Manager to go to that location and copy those image files to your root DAZ Content Library root folder under Presets/Materials and create nested directories under Materials <Your Name (or whatever)/<Genesis Version - Genesis 8>/Female/<Your Special Name You Gave that Character>/ and paste those Brow Remover Files there.
Then in DAZ Studio for each of the surfaces that are using those files you just copied to your personal character(s) folder(s) change the texture or image map used from the temporary location to the new location. After you've done that then save the scene.
It is optional to rename those diffuse textures and image maps to a naming scheme that is similar to the names used by the texture set before Brow Remover copied those, edited them, and replaced them with it's version.
Oh my god! That's exactly what I'm using! Thank you so much this helps alooooooot!
Example locations of DAZ 3D character textures before Brow Remover changed them:
D:<DAZ Content Library root path>\Runtime\textures\DAZ\Characters\Genesis8\Victoria8\
Example location of the temporary location of the Brow Remover temporary files:
C:\Users\<UserID>\AppData\Roaming\DAZ 3D\Studio4 Public Build\temp\
Example made-up personal location that I would copy the Brow Remover Victoria8 edited face textures & map images to:
D:\<DAZ Content Library root path>\Runtime\textures\<UserID>\Genesis 8\Genesis 8 Female\<Special New Name for edited DAZ Character textures>\
Where <UserID> is something like nonesuch00
and
<DAZ Content library root path> is something like \Documents\Design\DAZ 3D\Library\
and
<Special New Name for edited DAZ Character textures> is something like Mary