*smirks* Read the clue carefully. I'm pretty sure you can understand when you will realize what you're facing.
You're not the only one to think the mansion is too dark. Maybe lightening it up a little won't be a bad idea.
About the arrows to indicate the doors, I did that in response to a criticism I faced for my game The Escapists for Driftwood's game jam. Some people didn't understood the rugs were actually indicating doors and a mouse user was confused to not access the room while clicking on it. So, for this game, I decided to show arrows to indicate a teleportation point the player can go through, similarly to Pokémon Fire Red and Leaf Green.
Thank you for the English lesson, I'll hopefully remember it for next time.
Good luck!