Hi Mike,
You should upgrade to the latest Event Calendar Pro since it has the needed changes for the search index.
Regarding the file drag and drop most likely there is some other script error happening on the page most ;likely caused by the update to the latest version of jQuery which dropped some features from its api. As a result some older jquery plugins and Artisteer skins need to enable the jquery migrate plugin which adds back the things that were removed from the newer jquery api. See the Important Skin changes for how to enable the jquery migrate plugin and other things that mat need to be updated since your previous version.
Also the drag and drop files is in mojoPortal 2.3.9.7 not 2.3.9.6, did you upgrade to the latest version?
Hope that helps,
Joe