Trapped doors don't trigger when opening the door.
I approached a door. I wasn't adjacent to any other door. I try to 'o'pen the door and it asks me "which door?" so I hit 8 to indicate the door to the north of me. "You open the trapped door." I feel like it shouldn't ask me which door if there is only one, and that opening a trapped door like that should trigger a trap. Perhaps traps just aren't implemented yet.
It's possible that you had to choose direction for door opening because of the game recognizing the room-corridor transition as a door too (and thus it might have nothing to do with the not-yet-working-trap)