Every time I start the zenOn Editor it crashes before I am able to do anything!
In this case try following:
Delete the files Settings*.dat and SpecialList*.dat .
You find these files in the user directory, default "C:\Dokumente und Einstellungen\\Lokale Einstellungen\Anwendungsdaten\COPA-DATA\zenOn\Editor" .
Instead of the star there is the zenOn version you work with, e.g. if you work with zenON 6.20 SP3 the files are Settings6203.dat and SpecialList6203.dat.

Additionally try to rename the zenon6.ini, the editor will create a new one which is more or less empty!