That'll be it in a nutshell :p
Kinkless requires 10.4.5, OmniOutliner Pro 3.6 beta 2 and above. So it seems Kinkless is not for you at the moment. I would try the Export to iCal script in the ones I linked to. As you are 10.3 IIRC, you need to put the Export to iCal script from the OmniGroup web pages in ~/Library/Application Support/OmniOutliner/Scripts/ (or Pro) to have them appear in the scripts menu that appears in the application menus itself.
Kinkless requires 10.4.5, OmniOutliner Pro 3.6 beta 2 and above. So it seems Kinkless is not for you at the moment. I would try the Export to iCal script in the ones I linked to. As you are 10.3 IIRC, you need to put the Export to iCal script from the OmniGroup web pages in ~/Library/Application Support/OmniOutliner/Scripts/ (or Pro) to have them appear in the scripts menu that appears in the application menus itself.