bic mean char file. localvault hold all bics wut can be used for play. NPC mean blueprint. Export blueprint file with erf to other mods.
Different data stored in two kind of file. Only way to play NPC is open toolset, look at blueprint, use create for make same HD, race, skill, ability, inventory... all that stuff. Mite ned custom create app like PRC, leto or other that make custom race like tiefling, undead, etc. Ur problem is bic needs more data than blueprint have so ned to fill in all that with edit. Much more easy to just make with create in-game.
http://nwntool.coucou.net/ have diffrent way to make bic file than in-game. mayb try that.