Something odd I noticed

Here in MKPC, when deciding random CPU, the game only chooses from Mario up until the first Not-Unlocked Character Space. Because of this, if you unlocked all player-made cup characters (Bowser Jr, Rosalina, Diddy, Dry Bones, Funky, and Toadette), but not all the in-game cup characters, the game will never choose those 6 characters as CPU.

But they will appear if you play as them??

So. Do you notice how the characters you unlock from Custom Track Grand Prix come AFTER the ones you unlock from the non-custom track Grand Prix? Because of how the game checks which characters they can use as Computer Players, unless you have unlocked Koopa, Waluigi, Shy Guy, Birdo, King Boo, Hammer Bro, Dry Bowser, Petey Piranha, and Link, the charcters you unlocked from Custom Track Grand Prix cannot be used by the computer players. You can still play as them, but the Computer Players can't.

Hopefully that was easier to understand.