I will admit upfront that I have not actually used this component.  I gave it 1 star hoping more people would read this.  I did not use this plugin because it failed my initial review of the component.  For PDF files it uses a Google Docs web service and for MS Office files, it uses a Microsoft web service.  This means the Google or Microsoft site downloads the file in order to generate the preview.  YOUR FILES DO NOT REMAIN PRIVATE.  This information should be upfront in the description of this component.  If you're building anything that requires security, this may not be useable for you.