I'm no expert on AppleScript but the problem seems to be with the Mail rules and script trying to process the "Reminder" reQall. You only need the "Added" emails to be processed into OF actions (the reminders are just tha, reminders of the same info contained in the "Added" emails).
So, add a rule in Mail that says only process emails from
post@reQall.com whose subject line begins with "Added:".
I've attached a pic of the rules I use (I'm using the Script included in the above post - the one tweaked from JotNot)