I've to report a little bug in the game (LESSER SPOILER)
When you check all the four staff rooms you get a clue, but if you pair it to get a deAduction and then you check one of the rooms again the interested clue turns uncircled again, standing clear until the end of the game. This does not affect the final score or the deaduction got from it, but still may be confounding for some newbies.
That being said, I truly enjoy the game series and the clues&deaduction system! I played the games on ArmorGames and I had no problems to replay them here on NewGrounds, even if just for the medals.
PS: Another thing I noticed while replaying the series: why did you add an italian translation on ArmorGames but not here?