? great!
Now it works.
Both declarations (Initialize and Initialize2, like attachment) are necessary?
The first code (with ~) is the ID APP, the second (with /) is the ID banner.
I understood that Initialize is used only for the default size (320dip x 50dip).
With AdMob object, ID Banner is managed using mwAdInterstitial object.
Using FirebaseAdMob where ID APP must be placed?