Down open and up open door lights are used to add realism to your level.
Without lighting effects the level is going to... SUCK.

Down door lights is SE 8.

To do this

1)Put a Sector Effector with an original Hitag and a lotag of 8 in the door
  sector

2)Copy that sprite and put it in the room.

3)Hold alt and hit - to darken the room.

4)Aim at the SE and hit + to make it the brightness that the room will change
  to when the door is open.

THE same holds true to up open doors.  Except the SE is lotag 9.

