Thanks!
Regarding the AI, the dudes' basic behaviour is following the checkpoints on the track choosing randomly where there are alternate routes, if another dude is in front and within range there's a chance that they will be pushed out of the way and finally if an obstacle activates in front of the dude they have a chance of avoiding it by jumping or halting depending on the type of obstacle.
I built a sort of state machine to manage what the dudes can do at any given time