You can hold the R Button to make a sharp turn while flying or swimming. However, Bottles does not tell you this at any point in the game.
The voices in the game are not real speech, but rather a looping of voice-like sounds when text bubbles were displayed. This artistic choice was made due to memory limitations on the Nintendo 64 cartridges.
Beneath the name of the ship in Rusty Bucket bay it says: "Twycross, England" the location of Rareware HQ
Out of the five transformations in the game, the crocodile is the only one that can attack.
There was a level in the beta version known as Fungus Forest. The level was scrapped and reintroduced into Donkey Kong 64 (1999) as Fungi Forest.