That's how it would have been in the old version of the editor that shipped with DoS 1, yes. However, if you play that three player castle-courtyard arena map in DoS 2 EA, you'll notice it looks like they have a new system. The lighting inside the houses is different at all times than it is outside. Idk how they did this. Maybe you can draw an area in the map editor that you want to designate to be indoor and change the lighting there without relying on triggers this time around?
That is exactly what DOS1 does.
The area you draw is an atmosphere trigger.
