Issues with Xamarin Forms 4 using CollectionView in UWP project

Hello I'm facing some tricky bugs while trying to use the new CollectionView feature implemented in Xamarin Forms 4.
When i'm initializing the Datatemplate the entrie screen turn out white but if If I remove all the DataTemplate from CollectionView.ItemTemplate, just leaving it blank like this

`
<CollectionView.ItemsLayout>

</CollectionView.ItemsLayout>
<CollectionView.ItemTemplate>

            </CollectionView.ItemTemplate>
        </CollectionView>`

then the page gets rendered an CollectionView shows ItemSource elements with messy layout (without margin and padding, and calling toString method of element to visualize it inside cell)