This happened in another component last night, but was too tired to diagnose
However a much more simpler component, once downloaded (works fine in sandbox) is showing the same problem.
I complete a form, (admin sections) and click save I get a blank screen. When I turned on full error reporting, I see the following
Notice: Undefined index: creation_date in /home/fgwadmin/public_html/administrator/components/com_rtcallout/models/manager.php on line 344
Notice: Undefined index: modification_date in /home/fgwadmin/public_html/administrator/components/com_rtcallout/models/manager.php on line 347
Catchable fatal error: Argument 1 passed to RtcalloutCkClassControllerItem::postSaveHook() must implement interface JModel, instance of RtcalloutModelManager given, called in /home/fgwadmin/public_html/administrator/components/com_rtcallout/classes/controller/item.php on line 898 and defined in /home/fgwadmin/public_html/administrator/components/com_rtcallout/classes/controller/item.php on line 609
This also occurred in another component, but that was with front end editing, I have not captured that error yet but I will add it soon.
My Joomla version is 3.3.6