On this page you can see the integration with jdownloads. By making custom fields it is possible to choose how to show a pdf file for each download.
PDFViewer tag placed in layout {pdfviewer jdownloadsid={file_id} viewer={jdfield 8} style={jdfield 5} filename="{file_name}" search={jdfield 2} page={jdfield 3} showpdfpreview={jdfield 7} }
Show in popup and search for "recording"
Preview is disabled for this file
open embedded on page 9
Show page 3 as image in popup