Visible crew/equipment: In episode 4, look out for the legendary "Hand of Sutekh" - a hand (presumably that of a member of the crew) holding the cushion down in the scene where Sutekh stands up.
Visible crew/equipment: In episode four, after Marcus opens the second door in the pyramid (the one with the hidden switch), someone wearing a white shirt can be seen through the opening.
Visible crew/equipment: Episode 1: After Sarah teases the Doctor a bit when he's being somewhat moody, just as the TARDIS is suddenly thrust off its flight path (which was back to UNIT), Sarah and the Doctor are thrown about in the wonky console room (because the camera turns sideways), and the second camera becomes visible at the left side of the screen.
Answer: In 'The Five Doctors', three separate Cyberleaders are definitely used. So it's likely that Cyberleaders are like unit commanders, of which a fair-sized army might have several.
Daria Sigma