When you enter Life Support through the Cargo Bay, go straight ahead into the Atmosphere Control Room. Proceed to the back right corner and look for a maintenance shaft. Use the Gloo Cannon to get into the Oxygen Flow Control Room. Look at the note to get the storage room code. Return to the room you started in, and use the grav shaft past the electric floor. A Nightmare is probably already waiting for you downstairs. The storage room is just right from the grav shaft. Inside is the Nullwave Transmitter fabrication plan in a closet. The Nullwave Transmitter disables Nightmares and prevents them from launching its heavy attacks.