After the WordPress maintenance release, the plugin, still at 3.9.3 is not working. It appears to be something related to resolving URLs.
The database looks OK in that events are visible in edit mode, but they cannot be viewed in calendar format in “view” mode. And the calendar itself cannot be viewed. All returns 404’s.
Most of today’s reports appear to be on Event vers 3.11 so my installation still on 3.9.3 may be helpful.
I saw suggestions here to reset Permalinks and to check for conflicts, so I will do that and post back if there is any additional information.