Odd quirk
 

... Tell me I'm not going mad. When the Nav+ is locked- not just off- the windows do not do the 'one touch' up and down. Or is this another premium feature of the car I've missed?

If the battery is disconnected, the windows wont do one touch up/down until they have been manually wound down and up fully once. No connection to the Nav unit, but disconnecting the battery would affect both devices +++

Ah, thanks...

I thought there might be a correlation to something other than the Nav unit but couldn't quite fathom it!

It tells yer in the book......

I still find things in there!