TaLL0n

UPDATE: I found a few work-arounds. To fix the female hold-guards, I downloaded and installed this mod using NMM: http://www.nexusmods.com/skyrim/mods/37956/? To fix the female Stormcloaks, I downloaded and installed this mod using NMM: http://www.nexusmods.com/skyrim/mods/8852/? - Warning: it replaces the whole set with something else (ancient nord / draugr armor) but I rather like the new look.

I too have this same issue, but instead of using UNP, I'm using CBBE. I've noticed that even when I uninstall my armor mods (using NMM) the boots on my female Stormcloaks are still invisible! Very peculiar!