Thank you for your feedback ! I agree with you about the texts, we need to push further our English skills if we want to build a better dialogue-based game.
For the object placement, we were limited in time and couldn't draw more rooms (I was the improvised artist for the backgrounds) So we had to place the last puzzle into already existing rooms and used the real ghost to give hints to the player. The cage key is the most difficult object to find and it's totally my fault.
Again, thanks for your feedback ! Your comment is highly appreciated !