I get this error every time when the flamethrower is about to shoot.

General protection fault!

History: (FlameProjectile suburbs-3.FlameProjectile0, Function AWPStuff.FlameProjectile.PostBeginPlay) <- UObject::ProcessEvent <- (FlameProjectile) <- ULevel::SpawnActor <- (FlameWeapon suburbs-3.FlameWeapon0, Function AWPStuff.FlameWeapon.Streaming.Tick) <- UObject::ProcessEvent <- AActor::Tick <- TickAllActors <- (NetMode=0) <- ULevel::Tick <- TickLevel <- UGameEngine::Tick <- UpdateWorld <- MainLoop

EDIT: I've also tried installing the d3d8to9 and the 4gb patch like the creator suggested, yet it still crashes. I've also tried to install it without the polish version and the xPatch v3.1 mod but it still crashes.