Thanks toy for the support
but i've just solved the problem!

at last after 1.000 try it has ejected the CD.

than i've burnt a new CD (on a TDK disk this time) and in 3 minutes
my MK4 was updated!

VERY nice graphic! now i have only to test. but now here in Italy
is 23:53... and tomorrow i have to work.
i'll try it tomorrow going to work

thanks for helping me and the quality of virgin CD does matter!