We've just updated the package to include version 2.8.2a as there was a "work in progress" item left in the new update. This caused some debug to show on the first tab of event creation or editing... and a broken detail article selection. This is now fixed.
Beyond fixed... it's improved so now the user will not see Joomla categories or articles in those dropdowns that they do not have access to based on Joomla ACL.