I have some questions about this game. First to unlock N. Tropy do you have to get all gold relics or go to time trial mode and get the best record there? Also in CNK challenges do you have to collect all the letters and finish in first place to get the token? Because I had a hard time collecting the letters, but I got them all and finished in 8th place, but didn't get the token. Also to unlock pura and fake crash do you have to get 50 boosts in one race? Do they have to be fifty consecutive boots?
Thanks to anyone who can help me or who bothers to reply.

I have the PS2 version but I'm assuming it's the same in this version:

For N. Tropy, you need to go to time trial mode and beat his ghost.

For CNK challenges, you need all the letters and get in first place.

For Pura and Fake Crash, they do need to be 50 consecutive boosts. Also, you need to get them in an adventure mode race, not just any mode.