I installed Lyx (Processor) from the Ubuntu Software centre (Precise). It allows me to create and save Lyx documents but only allows me to view the PDF/PS rendition. Is there an additional package I need to install to have this functionality?
I finally discovered the answer to this question and for the sake of good housekeeping have answered my own question
I resolved this by installing Document (PostScript, PDF) viewer (GTK+ version) (evence-gtk)