I just made this integration following the instructions in the manual.. but now I wanted to filter the events in OVO that are supposed to open tickets in SD. Do I have to customize the OVO-SD.vbs script or can this be done only by modifying rules in the policies provided by the integration package?
No need to modify the integration script. Filters can be set up on the OVO side. You have to modify the policy named "Forward message changes to Service Desk" to trigger only for the messages you want to forward to SD.