|N version||1.4 and later|
Jump over to the exit door, and then up to the ledge above. Wait until the drone comes up to get you and charges at you. Dodge him and climb upwards. When you get as high as you can go, drop down to the slant on the left, and allow the floorchaser to come to the edge close to you. Drop down onto the wall and walljump over the floorchaser and run to the left, opening the exit door and landing on the ledge above the chaser. Jump through the gap to your right, over the other chaser, then essentially go back the way you came up.
INSERT ANOTHER METHOD HERE