Thanks for the replies guys, but no go.
What I have is a Logitech Rumble Gamepad F510, and it is certainly not registering the 'long press keys' like Left analog, Right analog, LT and RT for anything except the Acceleration, Brake, Left, Right and Clutch buttons. The other buttons like Camera, Horn etc simply revert to default if the same trick is used.
As the keys do seem to work for certain buttons, and they seem to work fine in other games, I don't think its a driver/controller issue.
Weird, looks like I'm the only one with something like this.
Anyhow, takes away nothing from the game, I'm enjoying it!