Here is the full list of all 26 Melissa K. and the Heart of Gold Collector's Edition achievements.
Beat all the best scores
Finish all puzzles in the highest difficulty mode
Finish all hidden object games with 90% or better accuracy
Collect all the Reclining Buddha statuettes
Finish five hidden object games in less than 20 seconds each
See all videos, view all extras, finish all extra puzzles and find all hidden objects
Use 50 or more hints
Finish all hidden object games without using a single hint
Release and cure all of the game's animals
Collect all the secret letters
Finish three hidden object puzzles with 100% accuracy
Watch each cinematic and dialogue screen from beginning to end without skipping
Finish the Collector's Edition adventure
Gather 200 objects in hidden object games
Finish the main adventure
Make a 10-combo in the final door puzzle
Lose the final door game 10 times
Write 30 diary pages
Touch the rat at least once…
Find the hidden pea…
Finish 10 puzzles in the adventure without skipping one
Complete five hidden object games without using a single hint
Gather 50 inventory objects
Explore 12 different locations
Travel back and forth five times between the same two locations
Send the Gecko to 10 places he won't go