ICal move events from one calendar to another with AppleScript

Question

I made an AppleScript to clean up my calendars and thought I would share. My iMac had a calendar called "Home" and my iPhone had a default calendar "Calendar" so I ended up with all of my events spread across two calendars. Decide to clean up and move everything to one calendar.
This script is admittedly not very efficient. The nested repeat loops means it takes a while to run. Feel free to take this as a start point. I have it checking each property for missing value before adding it to avoid errors. I could have added a line to delete the old event after creating the copy, but I was just deleting the whole old calendar after the script ran.
I hope this is helpful to someone. Oh, this was created under Snow Leopard so if you are in Lion you might need to tweak things. I don't know how much the scripting library has changed.
tell application "iCal"
          set thisCalOld to calendar "OldCalendarName"
          set thisCalNew to calendar "NewCalendarToMoveEventsTo"
          set cntrMatch to 0
          set cntrCopied to 0
          repeat with thisEventOld in events of thisCalOld
                    repeat with thisEventNew in events of thisCalNew
                              set isOKtoProceedWithCopy to true
                              if (start date of thisEventNew = start date of thisEventOld) and (summary of thisEventNew = summary of thisEventOld) then
              --Don't copy
                                        set cntrMatch to cntrMatch + 1
                                        set isOKtoProceedWithCopy to false
                                        exit repeat
                              end if
                    end repeat
                    if isOKtoProceedWithCopy then
                              set theStamp to stamp date of thisEventOld
                              set theAllDay to allday event of thisEventOld
                              set theURL to url of thisEventOld
                              set theRecur to recurrence of thisEventOld
                              set theEndDt to end date of thisEventOld
                              set theClass to class of thisEventOld
                              set theStartDt to start date of thisEventOld
                              set theDesc to description of thisEventOld
                              set theSummary to summary of thisEventOld
                              set theLoc to location of thisEventOld
                              set theExcludeDt to excluded dates of thisEventOld
                              set theSeq to sequence of thisEventOld
                              set theStatus to status of thisEventOld
                              tell thisCalNew
                                        set thePropList to {}
                                        if theStamp is not equal to missing value then
                                                  set thePropList to thePropList & {stamp date:theStamp}
                                        end if
                                        if theAllDay is not equal to missing value then
                                                  set thePropList to thePropList & {allday event:theAllDay}
                                        end if
                                        if theURL is not equal to missing value then
                                                  set thePropList to thePropList & {url:theURL}
                                        end if
                                        if theRecur is not equal to missing value then
                                                  set thePropList to thePropList & {recurrence:theRecur}
                                        end if
                                        if theEndDt is not equal to missing value then
                                                  set thePropList to thePropList & {end date:theEndDt}
                                        end if
                                        if theClass is not equal to missing value then
                                                  set thePropList to thePropList & {class:theClass}
                                        end if
                                        if theStartDt is not equal to missing value then
                                                  set thePropList to thePropList & {start date:theStartDt}
                                        end if
                                        if theDesc is not equal to missing value then
                                                  set thePropList to thePropList & {description:theDesc}
                                        end if
                                        if theSummary is not equal to missing value then
                                                  set thePropList to thePropList & {summary:theSummary}
                                        end if
                                        if theLoc is not equal to missing value then
                                                  set thePropList to thePropList & {location:theLoc}
                                        end if
                                        if theExcludeDt is not equal to missing value then
                                                  set thePropList to thePropList & {excluded dates:theExcludeDt}
                                        end if
                                        if theSeq is not equal to missing value then
                                                  set thePropList to thePropList & {sequence:theSeq}
                                        end if
                                        if theStatus is not equal to missing value then
                                                  set thePropList to thePropList & {status:theStatus}
                                        end if
                                        set theNewCopy to make new event at end with properties thePropList
                              end tell
                              set cntrCopied to cntrCopied + 1
                    end if
          end repeat
end tell
display dialog ("Exists(not copied):" & cntrMatch & "  New Copied:" & cntrCopied)

Answer 1

That should not be necessary because I get the value of ID out of another table, where I generate ID with a sequence..
So normally it should just tranfer that row from one table to another. But it doesn't !
Knowing that I cannot create a row in the table wouter_published_posts(I can just move rows from the add_post table to the wouter_published_posts table), It should be inpossible that twice the ID appears. But yet he keeps trowing errors...
help me, please