Here is the full list of all 18 Brightstone Mysteries: The Others achievements.
Checked in the hotel
Found the hiden note
Unlocked flower shaped lock
Visited/Played every attraction (without skipping!)
Assembled the board
Entered abandoned house
Opened the hidden door
Completed the maze
Entered the factory
Escaped the pit
Unlocked the safe
Made a perfect cup of coffee
Tranquilized the rhino
Collected all rings
Completed the game
FInish all minigames without skipping a single one
Finish all Hidden Object scenes without using hints
Finish the game on Expert Mode, without skipping any minigame or usining hint at all!