Regarding the convex wheel this is what I was told to do and it help with the wobbling wheels …
“delete the 4 wheel bones from skeleton tree in physics assets so you just have the root Bone only in the window where you generate the bodies”
Regarding the Video, you told me to put it on a blank plane which I did. It doesn’t do much because it won’t move. That’s why I asked for the engine input .ini file as i haven’t got access to the example project