I downloaded your sample for the PDFViewer and it works
Then i cerated a new PCL project in Visual Studio 2017
I added the PDFViewer package to the portable project and also added it to the Android project
I then added the sample PDF file to the Assets folder in the portable project and marked it as embedded resource
I then added the PDF control per your documentation and added code to load it in OnAppearing as per your documentation
it looks like the stream is loading correctly but the PDF control is not loading the PDF file properly
attached is the project that does not work
thanks
Mike