Second, there was a list of secrets on this forum that mentioned using the Laserdisc with Tova's invisible artifact. What's that about?
I've only checked it in the game script, but apparently you have a different dialog with Laserdisc (one of the Bell door guardians) if you've done Tova's quest: you have to give away 5 artifacts, but one of them is the invisible one.
I printed out a map of the level and crossed off paths that were impossible. Eventually I narrowed these challenges down to the correct paths. Neither challenge requires you to do anything difficult other than finding the correct path. Finding these paths yourself is the true reward. Papyrus is especially satisfying to figure out.
Anyone have any hints on the Papyrus challenge? I've spent at least 5 hours on it with no success.