To open the door and escape from the room in the game, follow these steps based on the game's features and storyline:

1. Explore the Art Gallery: Since dad and Liza are trapped inside the art gallery, start by exploring the surroundings. Look for clues within the various themed rooms, which include retro cars, the Middle Ages, animals, and space.

2. Solve Puzzles: The game includes various puzzles that you need to solve to progress. These puzzles are likely integrated into the room escape aspect of the game. Pay attention to the plasticine graphics, as they might contain hidden clues or mechanisms to unlock the doors.

3. Find the Differences: The game combines the "room escape" genre with "find the differences." Look closely at the pictures and scenes within the gallery. Finding the differences might reveal keys or codes needed to unlock the 12 locks on the doors.

4. Use the Clues: As you find differences and solve puzzles, use the clues to unlock the doors. Each lock might require a specific action or item found through the puzzles or differences.

5. Listen to the Music: The funny music mentioned in the game features might provide hints or change when you're close to solving a puzzle or finding a crucial difference.

By combining these elements—exploring the themed rooms, solving puzzles, finding differences, and using the clues—you should be able to open the door and help dad and Liza escape from the art gallery.