on respawning I found that "flags" was undefined. I placed several flags in my room (room E11S5) and it is still undefined. I then placed a memory watch on one of these flags, and the memory slot was labeled with an 'invalid path' message.

room E4S9 i'm running the code

creep.transferEnergy(creep.room.controller)

and this returns a -7. Are controllers not a valid target for transferEnergy?

HAH, i figured it out, sorry for the dumbness, I'm kind of new.

I tried to execute this code in room E4S9 without result:
Game.creeps.Harvester.moveTo(Room.controller);
The creep does not move.
I then tried typing 'Room.controller' into the terminal, and it returns 'undefined'