Well, I traded her in against a 2008 Maserati GT. Gorgeous car, however with the same problem later on.
For the XKR they adviced me to wait with repair of the head liner, till the front screen needed replacement...
Cost approx. £3000
(The back up plate which holds the liner cannot be removed in one piece, without removing the front window.)
My suggestion was to split the head liner in two halfs, left and right, to make a satisfying repair, but it never came to that....