It's been solved by change back to English language, perfect. Thank you very much.

Hello harry:
I've reinstalled Petrolhead, and want to use add-ons to upgrade the grand prix viersion(I've brought it before). So we I click the 'add on' button, but the program will shut down automaticly. And I alos found that when I click 'Sensor List' - 'All', it will also leads crash. (Before ...

Hello Harry
Recently I bought a onboard cam called "AMKOV SJ5000", it's very similly like a gopro cam(both the size and function) that have wifi control.(I've tested that from my iphone, it can take picture and videos).
I tried to connect it to laptimer(grand prix edition), but it seems not work ...

Hello. I update to the "Grandprix" from " Petrolhead". When I reinstall the " Petrolhead" and want to use the multi cam, it's shows that my version not support this. Then I go to plus to active "Grandprix", It's still ask me to pay for the money. So anyone can told me how can I get it back?