I've been trying to get the "Lock List" function to work on doors for custom NPC homes, but the doors never lock when they leave/sleep. What's the method for getting doors to lock/unlock properly?

Id imagine you make a key and assign it to the door. Then equip the NPC with the key.

That's how you COULD do it but they have introduced the "lock list" which as I understand it fundamentally it works by allowing that to be done automatically.