After watching some YouTube videos of the 2017 races of F1 and Porsche GT3 Cup, I've recorded a new fast_lane.ai and adjusted the ai_hints.ini to prevent too much accidents in the first lap of a race. It's still not perfect, but it should work fine with the Ferrari SF15-T, the RSS Formula Hybrid 2017, the Porsche GT3 Cup 2017 and other GT3 cars.
There may be cars that won't get around Loews corner, because of missing steering radius.