SealMan87I'm fairly certain it was a time trial type event, with a prize for the person who did the best. Those all close eventually too.
I was going to beat these on a new account to easily rack up a ton of money, and they are closed? That's a shame. I can't say I understand what the benefit is here. They are simply reducing the functionality of the game needlessly.
Go do the Kei-Car seasonal 15 times and you have your 6 million CR.
Takes only 45 minutes to get this cash.
raVer