Does Opus have a way that PDF files content can be seen in thumbnail view? Thanks
Opus will use whichever PDF thumbnail generators are installed on your system.
Some (although not all) PDF viewers include thumbnail components.
If you are using Adobe Reader, you'll need to install my Adobe Reader 64-bit fix for its thumbnails to work correctly on 64-bit Windows, because Adobe are muppets. 
Magnificent! This will eliminate the need for unnecessary programs. Thanks