[Plug-In Events Calendar] Blank White Page

There had been an events calendar with about 10 events post to it for the months of August through November 2010. I was adding some events (about 6) and when I was done, I noticed that the events calendar had disappeared, no error messages, just a blank white page. Has anyone come across this problem and how to solve it. I would prefer not to start over. Thanks for your help with this. The website is http://www.namimass.org