On WinPhone 8.1 Xaml (WinRT),
for anyone who got a problem working with the new prerelease CC 1.7.0 pre1 with Xamarin forms 188.8.131.5284...
I had a problem activating the game from a second page (NOT the first) like in the project attached here.
I got an error of "Access Violation" when pressing the button and trying to move the second page (the CCGameView page).
I found a solution for now.
DOWNGRADE to XF 184.108.40.20671.