This sounds like it could be a Plugin Firewall issue. Do the standard BPS Pro troubleshooting steps in the link below to confirm, eliminate or isolate which BPS feature is blocking this plugin. Check your BPS Security Log for any log entries related to the EventOn WordPress Event Calendar plugin and post that log entry.
http://forum.ait-pro.com/forums/topic/read-me-first-pro/#bps-pro-general-troubleshooting