Do this to play any vehicle on any track you want: start the game with racing
-car ##, replacing the ## with the names of the vehice file of your choice
(the list of *.vhc files is in the bigred directory). Then choose your track
in the game.
Hidden Tracks:
U.S.A.: Use the boat with the big propeller. Go off-road to the left. Some of
the hills are tough to get up, but at some parts of the track, the hills are
very small. If you get up you'll find many awesome jumps, a few gorges, and
alot of ways to get fliped over.
Japan: Use any vehicle. Go off road to the left again. Or if it's too much
trouble, at the first "Gate jump", follow the water to the left. You'll find a
"Gate jump" surrounded in slippery water. To top it off, the track's
surrounded by incredible jumps.