Done a bit of testing. 5 second penalty system seems to be out of order. It's engaging penalties for fully using the curb.
This is very dangerous as your tires get used up, the car tends to go wider and wider, which means you'll be sort of picking up penalties a lot. It's also inproper if you try to brake early and by a mistake use too much of an inside curb, you get hit by the penalty again. It ruins the entire experience this little bug in the track. I'd suggest running without the 5 second penalty system for this race, since there is no way to gain time by cutting any part of the track. Not even last chicane as there is a sand trap.
For what I know, running wide on the exit curb costs enough time by itself, especially if you get on the grass too.