1-If you push the Y key while you play you can change the your character's outfit! (after you chose one)
2-If you push the Z key It will highlight all clickable objects!
3-The Control key "reloads" the screen,the only effect that i noticed it did was in the panoramic view of the town and at the lighthouse screen.
4-The Left and Right arrow keys can help you navigate the menus during the game.
I don't know if there are more but there might be!