Crazy texture/mesh glitch

[yic17]

Hi.

 

Lately I've been porting many follower & armor/weapon mods from Skyrim to SSE with no problem. I followed the procedure of re-saving the esps in Creation Kit and optimizing the meshes using NIF Optimizer. But now I came across a weird glitch I can't solve.

 

I'm trying to convert this mod: http://www.nexusmods.com/skyrim/mods/69288/?

 

Followed the standard procedure but in-game her head is going all crazy like this: http://i.imgur.com/eS09lkH.png

 

So I tried optimizing all the meshes one by one. In the end I found out it's her facegeom NIF that's causing the issue. I used the other guide where I add "Has_Tangents" to each of her facegeom NIF parts. And turns out when I add it to her mouth part, that's what causes the glitch. However, beyond that I cannot figure out how to get it fixed. So can someone with mesh/texture experience help me out here?

 

Here's different variations of the facegeom NIFs in case you want to check their differences.

 

All parts no tangents (Original file): https://drive.google.com/file/d/0BxKqQVsldfzXWWFrbVV3SWVwQUE/view

All parts except mouth no tangents (Working but no mouth): https://drive.google.com/file/d/0BxKqQVsldfzXbWlxMVl0MmsyU2M/view

All parts has tangents (Glitch starts showing): https://drive.google.com/file/d/0BxKqQVsldfzXVEt5a0ZBNERZUjA/view