In Mudlet-2.1 (will be released on saturday) there'll be 2 more mapper features:
1. exit weights: setExitWeight(1849, "n", 5000) e. g. the northern exit means taking a boat trip that takes very long to reach the next room
getExitWeights(roomID) returns a table with the exit weight information in a room.
2. doors: setDoor(1849, "w", 3) e. g. add a locked door to room 1849, western exit.
getDoors(roomID) retrieves the door information of a particular room. Doors for standard directions are being visualized except up and down exits. Opening doors automatically via script should be trivial to script now.