It is not a full texture/material, it is just a simple set of jpgs. Any basic image editor should be able to open them and modify them without a problem.
Feel free to modify and the jpg's and make your own unique set of custom skins for G3F.
Please do not redistribute the un-modified set, I have made it freely available for everyone at ShareCG and here!
If you have any questions please let me know!
This is what the basic texture set looks like applied, nothing fancy, but a good starting point.
These are the original diffuse files that are used in this render, note the big change on the arms and legs which are now entirely separate images (in V4 and Genesis 1 and 2 they were in the same image) They have also moved the ears from the torso area to the head.