The Vulkar Update has been released, albeit without the droid component due to glitches in trying to give Vulkar NPCs the droid hide (an invisible item which makes a droid NPC immune to poison and such) via the TSLPatcher, time and patience will be key in fixing those bugs so I decided to release the main update now whilst the Vulkar droids will be added in an upcoming patch.
Anyway, I'd like to announce some good news for the project going forward... and this is something @LDR in particular would probably like to hear as well!
I have discovered what causes the 1st major bug I mentioned at the start of this thread, more specifically, the bug that causes this issue:
Those NPCs are all wearing different clothing items with texture variants from 2-8 yet they all show the 1st texture variant when it logically isn't meant to.
Here's the problem that causes that:
Let's take the NPC "dan14_setf001" from the module "danm14aa", she is a female Lite NPC in the vanilla game though in NPC Overhaul style mods she's often one of the many NPCs who are given a proper appearance with a piece of clothing. She, and all the other Lite NPC settlers in the "danm14aa" module, are all affected by this same mysterious bug.
Now let's take the NPC named "Jon" from the same module, he wears "g_a_clothes02" and as such his clothing texture uses the 2nd clothing variant, so why can Jon wear unique clothing yet the Lite NPCs cannot even though they logically should? What makes Jon different from the Lite NPCs?
The answer lies in the "Race" field in the UTC file.
Jon's "Race" is set to human whereas the Settler NPC is set to "****", I cannot explain why setting these 'bugged' NPCs from "****" to "Human" allows for them to wear clothing but that's the fix!
I'd like to give credit to SpaceAlex for this bug fix as he technically encountered and fixed this bug before me in his K1 Enhancement Pack mod all the way back in 2008, if it weren't for his modder's resource that allowed me to analyze his files this fix would not have been discovered today!
Whilst the bug isn't fixed in the latest release of the NPC Diversity Pack, I can assure users that this fix shall be applied to the very next update coming up.