Hi, contacted the third-party package creator.
He recommended to upgrade to latest version of VS.
I got a VS studio uppgrade alert today and upgraded.
This solved this problem.
Testing the official Map Control - Xamarin.Forms Map Control in another app (KaPang).
This package lacks some good functionallity that Xamarin.Forms.GoogleMaps provides but can perhaps be good enough for app KaPang?
Any official development plans for Xamarin.Forms Map Control?
This case can be closed.
archive IOS and published it in Apple Testflight a week ago and it went OK.