Hi, You seem to have "lost the texture". Typically, the texture files for skins are in the following folders, with extensions *.dds
Data\textures\actors\character\female
Data\textures\actors\character\male
Does this help?
I am doing the same thing in Python. It seems to work with Skyrim.esm, Wyrmstooth.esp and a couple of others. Let me know if you are interested in collaborating. https://github.com/sinanonline/SPyrim Also see this: https://github.com/TES5Edit/TES5Edit