Why does this AppleScript cause a big delay in Mavericks?

Question

Hello,
I use FileMaker for my database needs. I have been using an AppleScript to create a calendar event from FM to my Calendar using Apple Calendar. This has worked flawlewssly in Mac oSX 10.7 and 10.8. Every since Mavericks, the script still works (creating no error) but takes about 1 minute to complete. The funny thing is that if I run the script from the AS editor, it works just fine. The FileMaker does have access to my calendar in the security area.
Any thoughts?
Here is the script that is invoked:
launch application "Calendar"
repeat until application "Calendar" exists
          "delay 1"
end repeat
tell application "Calendar"
          set my_event to make new event at end of events of calendar "Test Calendar" with properties {description:"Test description here", summary:"Summary Text here", location:"location information here", start date:date "Sunday, December 8, 2013 at 10:00:00 AM", end date:date "Sunday, December 8, 2013 at 12:00:00 PM", allday event:false}
end tell
Thanks!
Stephen

Answer 1

set myCal to "MyLocalendar"
tell application "Calendar"
          set l to the title of every calendar
          if myCal is not in l then
                    set n to uid of (make new calendar with properties {name:myCal})
          end if
end tell