Time of day
While playing a game, press [Shift] + T.

Look down
While playing a game, press [Shift] + U.

Auto-level
While playing a game, press [Ctrl] + [Alt] + 5.

Jump to location
While playing a game, press P + [Tab] + T. Then, enter a location code and press [Enter].

Debug mode
While playing a game, press P + [Tab] + D to enter debug mode. Then, the following information will appear on screen:

Recon camera
While playing a game, press P + [Tab]. Then, press one of the following keys while the recon camera is active to activate the corresponding result: