Okay Ghostofmacbeth, I still must be missing a step because I just followed your set up and I'm still unable to remove the previously applied textures (bring the figure back to its untextured state after applying a MAT Pose).  Now, when I create the "blank" texture (using the original untextured figure) here's what I did.

1. I made sure my figure was selected.
2. Went to the Materials room
3. Selected 1 of its 10 materials
   4, Created a node for it (New Node -- 2D Textures -- image_map)
4. Left the image source as "None"
   6. Clicked on the "+" sign in the Materials Library to bring up the "New Material Set" prompt box
5. Named it something descriptive such as "Remove Textures"
6. Selected "Material Collection" option (as opposed to "Single Material")
7. Under the "Select Material" tab, I left ALL the materials checked/selected
8. Clicked "OK" to save
9. Converted the mc6 file by changing the line "mtlCollection" to read "figure" then clicked on "save".  Went back and changed the extension of that file from mc6 to pz2.
10. Transferred that pz2 file into the Pose library
11. Went back to the Pose room and loaded the figure, applied a MAT pose texture to it, rendered it to make sure the texture took, then tried to remove the textures by applying the "Remove Textures" MAT Pose file I just created, but the MAT Pose texture I previously applied was still there.  

Now could it be that my problem may be stemming from step #8 and/or #9.  Should I maybe "uncheck" ALL the materials instead of "checking" all the materials? 

Other than that, I simply don't know what seems to be the problem.  I'm currently testing this on Poser 6, however my intention is to make this workable in Poser 5, 6 and 7 (and possibly Poser Pro)

Vincebagna, thanks for that link, it's very useful.  :)

Thanks so far to both of you (Ghostofmacbeth and Vincebagna) for your help thus far, I really appreciate it.  :)

-J

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