Updated the plugin to new version released today. Seems to work. Bravo!
1. In the plugin's settings page I am getting the error
Warning: call_user_func() [function.call-user-func]: First argument is expected to be a valid callback in .../wp-admin/includes/template.php on line 1102
2. Why do you need to know username and number of fans to show in settings page? This info should be asked in the widget itself. That would allow people to use multiple copies of the widget via Dynamic widgets.