You can see the walkthrough of the full game including all achievements in the following video :


Main Hall 1st Floor
2:07 Collectible 1
2:35 Collectible 2
2:46 Collectible 3
2:55 Collectible 4
3:09 Collectible 5
3:25 Collectible 6

1st Floor Corridor
10:52 Collectible 10

1st Floor Study
18:29 Collectible 11
18:51 Collectible 13
19:13 Collectible 12

1st Floor Storage Room
23:23 Collectible 16
23:38 Collectible 14
23:50 Collectible 15

Main Hall 2nd Floor
28:26 Collectible 7
28:41 Collectible 8
28:50 Collectible 9

2nd Floor Corridor
40:34 Collectible 20

2nd Floor Bedroom
41:16 Collectible 19
41:35 Collectible 17
41:45 Collectible 18

2nd Floor Workshop
58:44 Collectible 21
58:58 Collectible 23
59:13 Collectible 22

2nd Floor Great Room
1:19:43 Collectible 24
1:19:55 Collectible 26
1:20:07 Collectible 25

7:57 Cryptographer : Use the Decrypted Code
13:04 Ceramics Expert : Solve the Vase Puzzle
16:17 The Abandoned Project : Solve the Wheatstone Prototype
17:49 Snooping Around : Enter the Study
39:47 Look at this Photograph : Use the Code in the Photograph
47:03 Child's Play : Open the Toy Box
49:10 Sharp Ears : Open the Musical Box
58:05 Tipping the Scales : Solve the Weight Puzzle
1:13:41 Security Expert : Open the Security Storage Box
1:15:32 Solving the Symbols : Open the Metal Cabinet
1:18:55 Eyes on the Prize : Reach the Great Room
1:20:09 Legendary Burglar : Find All Collectibles
1:22:37 The Cat Tax : Bribe the Cat
1:25:30 Stargazing : Study the Constellations
1:29:05 The Golden Prize : Get the Gold


Have Fun !