Issue with armour mesh.

[Deathmaw]

So I have converted this armour to bodyslide several times : http://www.nexusmods.com/skyrim/mods/18097/?

 

That always goes fine and it acts fine in game except for a small issue.

 

The skirt and belt will sometimes disappear if I look at them on a npc at a certain angle. When I move to a different view it is there fine.

 

Any idea what would cause behaviour like this?