I does this with every body paint I tried (from multiple mods). The bug existed in Oldrim (with the original mod) so it this not from the conversion. I don't understand how it can happen but the armor seems to override the UV mappings for the overlays. Is there such thing as UV layers? If so the armor is maybe using an "UV layer" reserved for body overlays. I'm new to the NIF format so I don't know how and where to look to find out.