vmanolova,
Thank you for the quick reply, the links you provided were quite helpful in diagnosing my issue.
What I hadn't considered, but which is covered in the article KM1150692 entitled "VuGen hangs when trying to use the 'Open Script' button", is that my problems began after disconnecting an external monitor from my notebook. I reconnected the external monitor in the same mode (extended desktop), attempted to open a script & the "open" dialog box appeared on the 2nd display. I was then able to open up the script and continue working normally.
Thanks again for your help!