For the acoustic lock, did you also enable the menu item in the MMI? As you have to do that, and then use the MMI to turn it on.
Acoustic Lock Menu in MMI
SELECT: Control Module 09 - Central Electronics
SELECT: Security Access - 16
ENTER CODE: 31347
SELECT: Adaption -...
It's there... (but no help to you as jot near car to show you how).
Not possible on VC.
The plus sign means there's a menu, use the jog dial and push to the left to bring up that menu.
Audi confirmed firmware bug for why reversing cam is not full screen on MMI with ghosted car sensor...