Hi Tim,
Thank you for your interest in Syncfusion products.
At present we do not support to prevent scrolling when view mode is set to One Page. We have logged a feature request for the implementation of this feature. Please follow up the implementation of the feature in the incident 132250 (https://www.syncfusion.com/support/directtrac/incidents/132250)
As a workaround we have developed a sample to get the pages of the PDF document from the PDF Viewer control and loaded the same in the FlipView control. Please find the sample in the link below.
Sample link: https://www.syncfusion.com/downloads/support/directtrac/132250/PDFViewerWintRT_20131018973348.zip
Please let us know if you need any further assistance.
Regards,
Suresh