Hello
I have edit the car list in Assetto Corsa and the last gear is 6 in the McLaren MP4 GT3 but I still get the flashing when I reach maximum in 6th gear !
Update :
Seems like all cars works the same in Assetto Corsa and that the "last gear" function in Fanaleds don't prevent the flashing to occur when you're in the highest gear.
However in RBR this feature seems to work.