it happened to me on ascari nsx event, it stored my time but stripped away my gold trophy and settings/parts i made/bought in that event. after this hard lesson, now i install all parts and do setups BEFORE i enter the event and SAVE there. as soon as you improve your time or apply major tuning to your setup you should exit out and save again.
it was weird that my time was well within gold time but without trophy - i had to reclaim it and got paid again. i cant be sure if i was paid twice, i doubt it, but this bug could be exploited to some advantage perhaps?
again, if you buy tuning parts while in the event and if it crashes, youll lose all of them.