Who started programming them at first, and it he still working on them? What are his plans for them?
Whales (whalesdev).
No. And he has no plans anymore. He is not working on CDDA.
Edit:
Your question is not that useful. Think you might want to know who is working on NPCs right now, and who added the additional quest line to NPCs. I have no idea myself.
Acidia was the last person to work on NPC’s IIRC. They tend to be a map person, but aren’t afraid of building quests that involve their map locations. The Sarcophagus, for example, is another of their additions to the game.