Open Pages in windows
How to a open a file with .pages extension.
Save the file to a folder
Rename it with a .zip extension (instead of .pages)
provided you have an unzip program it should open up.
Extract files to a folder then browse to the folder.
Now double click the folder "Quicklook".
You will find a file called preview.pdf.
Preview is a pdf of the original .pages document and Thumbnail is a .jpg of the document.