Freezes When Saving

I have an early 2011 Macbook Pro running Mountain Lion (I upgraded yesterday… prior to that everything was fine) and am experiencing a problem with saving. When I open Scrivener, edit an existing document and then proceed to save, the program freezes, leaving me unable to edit the document further or close the program. I have to force quit every time. Forgive my ignorance as I have not been using the program for very long nor am I particularly tech savvy.

Which version of Scrivener are you running (2.3.1?) and are you using the version from our site or the Mac App Store version?