Need help setting an executable to WinVista on a installer


I have problems setting Windows version to Windows Vista in a Steam Game (Assetto Corsa). This game only works (to me and a lot of people) with this Windows version. But in the last times Steam don’t start correctly if you use this option. If you configure manually the system to Windows7 and then you set the executable to Vista, the game works. But I don’t know how I can indicate this on a installer (I would like to modify the actual one with this configuration). Can you help me, please?

I’d suggest installing the game with Proton (in native Steam) rather than Winesteam. This way Wine bottle will be set up once correctly for the whole game, without extra issues caused by trying to mix it with different config for the Steam client.
Although proper install process would likely require protontricks.