Quote from SilverDarkBlade19
Would it be much of a setback to let NPC's realise they can use ladders? and open trap doors? more the ladders then the doors really. its quite annoying to have to build stairs for npcs instead of just making ladders^^ thanks.
I have several NPCs that climb ladders. Have you tried making a path and placing a waypoint at the bottom of the ladder, then a waypoint right at the top?