Window pane is blank; does not display the document.
I've checked the official website, but it doesn't appear to support version 12 of the Quick View Plus. All there is on the website belongs to version 13. However, I strongly recommend checking the FAQ page on the website and if you need additional instructions, use the email to contact the developers.
Official page: http://www.avantstar.com/quick-view-plus-standard-edition#fndtn-support
Note: Make sure to download the PDF file as well.