At the skull load-in screen, type the following case-sensitive text, with spaces as noted: "Roberto Dan R Zaphod B [Space]"
After you type "Roberto", Stauf will say, " Duh.... that's not it Karl!". Ignore him as he is trying to trick you. After the "B", type [Space], then any of the following letters to get to that point in the game:
a: End of disc one. s: End of disc two. d: End of disc three. f: End of disc four. e: The "Olive In Stein" riddle, good for using the Kellyn code. g: The very end, at the "Let's Make A Real Deal" intermission sequence.