For your points to count towards a Casino Race, make sure you join or rejoin a slot from the Casino Races menu.
When you open your slot game from anywhere else, you'll get a widget with the following message: 'Your Race is running Play'. Click 'Play' on each new slot to have your points counted in the race. If you see that widget and forget to click on 'Play', you won't get any points for your race.
Yes. You can use Casino Instant Bonuses in a Casino Race the same way you use cash. Bets made with an Instant Bonus will qualify if they meet the minimum bet criteria for that race.
If you're playing a particular slot during a Casino Race and your game is interrupted, that spin won't count towards points for that race.
If you're able to complete the interrupted slot game, you'll receive the winnings as usual.