Go up the elevator where there will be a room with a key. After getting the key, go back to the key activated door which leads to the tip of the boat. The other door in that room leads to a long hallway in which there will be a room on the left with a switch that opens the teleporting room. Going further down the hallway there will be a room with a switch. There is a staircase here which leads to another room with 2 switches (and also a secret in the corner - to the right as soon as you walk in. The secret room has two secret panels which have useful items). After hitting all three of these last switches the boat sinks.
Go back to the room with the teleporter, and you're done.