Hi Simon....welcome to the Forum
Great looking Audi :-)
Sorry, can't help with the first two questions but I certainly wouldn't throw away the bracket as it may be vital to the car...or not but you won't know until the day when you need it, lol.
The allroad setting, I would wait until the dealer has had a chance to look at it, but it may be something simple like the drivers door is open at the time and it won't feature until closed (like Range Rover, etc).
Cheers Trevor