It is a bug of this plugin when using on https. To fix the problem try the following:
Find and open the file functions_for_xml_and_ajax.php from the spider-event-calendar plugin folder. Then look for <script src=”http://ajax.googleapis.com/ajax/libs/jquery/1.8.0/jquery.min.js”> (there are two occurences of this) replace the http with https and save the file.
Regards
Jins
Hi creativemms I did you get any solution ? I am facing the same issue.