Thank you. I'm glad you enjoyed it. If you haven't played the Kemco NES games than I cannot recommend them enough. 'Shadowgate' in particular is a masterpiece and my all time favorite puzzle game. Shadowgate is about 4x larger than Infested. I hope you do play it as well because Infested actually has five hidden references to Shadowgate ;).
As for the extra items; those are red herrings. Much like in the NES titles there are far more items in the game beyond those used to solve the puzzles. It's simply to throw you off and keep you guessing.