Prism + Android

Hi List,
me again.
I got prism + UWP to work like expected.
But now a new Problem comes up.
I try a Solution from the Prisms_Templates (UsingModules) to run on a Sony Xperia with Android 5.0.2, i set the Project Properties to

-Use lates Platform
-Android 5.0 8API Level 21 - Lolipop
-use compile using SDK Version

all what i get is a NullReferenceException with the remark 'No Sourcecode available'
Any idea where to look or what i'm doing wrong.

The Solution run's perfectly as a UWP.

Thanks
Peter