"Any player may move any car of their choice, as long as the die has not already been used this round"
... fair enough, but what's the whole point then in this rule :
"When a player is handled the cup with ony one die, they return all of the dice to the cup before starting their turn... "
4 players : (black,white,green,red)
A plays the white die B plays the green die C plays the red die D must return all the dice to the cup,shakes it up and can only play the black die, as the other dice have already been played this round.
Only makes sense to return them all in a 2 & 3 player game.