The Steam version of this game has three achievements that didn't make it into the other versions of the game as far as I'm aware. They are all unlocked by using the Viewer item on different points in the diner before a particular color has been restored. Each achievement has two different points that will work; both are included below. I unlocked them in the order of the floor they were on (ground floor, upper floor, attic) but I've listed them here according to the number in the achievement name.