@AleX5:
Has your friend waited a while after upgrading the nav unit? When I downgraded to V26.09A, I first lost a heartbeat or two 'cause aux heating, phone, code and tv where gone, but after a few minutes all items came back.

I was playing around with the settings and every time I went back to the main screen pressing "Menu," another one of the missing entries has been back in place. Looks like the nav unit had to re-scan the bus to find all features installed.

BTW: the same always happened when I went back to V26 (+toggle3D)