Go to your game folder (where your game is saved).
Then go into the folder "game" and then into the folder "Quests".
In the folder "Quests", Find the file named "Achievements.rpy".

Open this file with a text editor like notepad or notepad++.
Scroll down to the bottom of the file and in the last line, change the false to True, like shown on this screenshot.

'Save the change you just made and then launch the game.
Open any save you have and go into the gallery.

This should have unlocked every single scene there is in ep1 and ep2.

Originally posted by author:

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