I have just finished the level Mad Monster Mansion and I cannot find the..

Before you enter Mad Monster mansion, follow the narrow path that leads to the entrance to Mad Monster Mansion and turn left in front of the entrance. At the end of this path you should see a grated door; knock it down to expose a path to a shanty at the bottom of the incline.

Now enter Mad Monster Mansion and exit as a pumpkin, then go down the path where the grated door used to be. When you approach the shanty, you'll see a hole in the door just big enough for you to enter. Go in the hole and you'll see Mumbo, a Tee Hee and a coffin. Go to Mumbo and he'll turn you back into Banjo at no cost. Now head over to the coffin and destroy the lid to reveal a water level button. Press this button to raise the water level in the chamber behind the 450 Note Door.

Now exit the shanty and go through where the 450 Note Door was. In the chamber you'll see a hole highlighted by two red eyes; you should remember this when you went to the Mad Monster Mansion puzzle. Once you go through the hole, you have two options as to how you can access the Rusty Bucket Bay puzzle:

1. Proceed to the Mad Monster Mansion puzzle chamber and locate a grille in the wall opposite the Jiggy podium. Smash it and go up the path until you come to an infested beehive and a path opening out from your left. Smash the grille in this path to access the Rusty Bucket Bay puzzle chamber.
2. In the chamber on the other side of the hole with the red eyes, resurface and look for a crate with the Rareware� logo. Smash it to reveal another water level switch, then press this switch to raise the water level in the chamber and those adjoining. Then, swim to the hole on the other side of the chamber. Go in this hole and turn right when a path on your right opens up, then smash the grille on that path to access the Rusty Bucket Bay puzzle.

Place 12 Jiggies in the puzzle to unlock Rusty Bucket Bay. The entrance is right in the room on the other side of the hole with the red eyes; selecting option A from the above will allow you to access the world while the deck is still dry but option B will force you to dive underwater to enter.