Ok, so I have 2 Skyrim setups, the Steam version & the GOG version, for different load orders.
I make follower mods, they have custom bodies & outfits. One of my followers, Hroki the Valiant, has outfits with golden jewelery pieces covering the neck, arms & legs.
On the GOG version of Skyrim, two of these mesh pieces (on the neck area) have an odd bug with the texture, as if the UV map is misaligned. However, it gets stranger:
1. This issue does not exist on the Steam version of Skyrim SE, the texture displays properly.
2. The outfit meshes are exactly the same in both my Skyrim versions. When migrating my mod from Steam to GOG, all I did was copy & paste.
3. In NifSkope & Outfit Studio, the texture also displays normally. The neck piece also has no distinct differences in the mesh from the arm & leg pieces which still display properly; they share the same shader flags.
4. In game, the texture appears to shift & move about depending on the camera angle, as if one was editing the UV map in Nifskope by dragging the vertices around & watching the texture change in real time.
Screenshots are included (as my followers are NSFW, sensitive areas have been blacked out). The one on the top shows the neck pieces as they are on the Steam version, the bottom shows the texture error on the GOG version.
Any insight as to why this has happened would be appreciated. Thanks in advance.