once a group has cleared a room and entered the next room: monster spawn, the room is set and the players spend movement to close the door. Once the door is closed can the OL spawn monsters in the previous rooms since it is now out of LoS. or is the OL limited to spawning in the current room.

thanks again for all the answers to my questions

Of course the OL can spawn there. The OL can spawn in any revealed area that is out of line of sight from a hero. If the heroes closed the door, you thank them for providing a convenient spawn location for you. Just remember that unnamed monsters cannot open rune locked doors.

excellent thank you.

its a slow work day so im thinking of questions that my group discussed during our first game the other night.