Schuey shouldn't have done that, full stop. He crossed the line before actually stopping in the pits but for some reason they allowed it. I expect Mr. Ecclestone had a quiet word with the stewards
AFAIK now, if you get a penalty in the last 3 laps, you can either stop before the end or get a fixed time added to your overall race time. (though that may be solely for F1)
I've done this in GTR (I think it was a cup race), there's no penalty, I finished in the position I should have, but I don't know if it added time on.
I think the head race organiser lost his job for the Schuey thing actually. You can bet Ferrari were just playing by the rules, its the person who drew up the rules who should get sacked, but that was probably Max.