I ran into a bug where when I put the core into the machine near the end of the game I guess I pressed a movement key at the same time the first time and it took the core but didn't put it in the machine. Similarly during this area the puzzle sequences were offered in a few areas and it broke in that I could keep entering keys and it would just keep allowing more entries. However, the fact that you incorporated a save system made it no big deal, I was just able to load my save game and complete the game. Great job.