Non Join-able NPC Portrait File Locations

[DrOctogonapus27]

Hi! I'm new to joining/posting on these forums, though I've used them extensively to get information on mods/the game in general. I joined because there was one bit of information that I could not find on these forums or any other BGII related forums/websites that I know of on the web, even the Mod building forums.

Anyway.. to the point. I have been messing with modding myself and adding/tweaking the game to my favor and I can't find information on where to look to add NPC to non playable characters, similar to how Bodhi, and the non-playable Bhaal spawns in ToB have the portraits on them. Where in the character/creature files is this located, and how would I be able to add portraits to them?

Thanks in advance for any help!

Also, I generally stick strictly to WeiDU mods, as they tend to (usually) be pretty compatible with one another and are extremely easy to make minor changes to. If you know of any that you love also give me any suggestions here!
I currently use the the offical patches and Baldurdash (non-WeiDU) and: G3 Tweaks, Valen, Solaufein, WeiDU Ascension, and Item Upgrade in pretty much every game. So if you have any other well developed mods please tell me!

One last thing, if anybody has any non-cheating strategies to beat the VanHelsing vampire encounter without cheats and using non-superpowerful PC's please let me know. I generally have to run that fight 30+times every game to get lucky enough to beat it or use the CLUA to keep reducing Valen's exp to 0 until the rest of my party is super high level.