You can run sd_event manually and specify the parameters in a commandline to test the integration. Normally, in the OVOW, you will set the troubleticketing option to on and specify the script to use which will call sd_event.vbs not the sd_event.exe. sd_event.vbs will have code inside to get parameters from the OVOW messages and then pass those parms to the sd_event.exe command.
You can find "howto" in the OVO_Integration_AG.pdf guide. see attach.
"This guide explains the integration between Service Desk and OpenView Operations for Windows and UNIX. With the information in this guide you can install, configure and perform the various tasks available with this integration."
If memory serves me correctly the integration paper had some 'inconsistency' as to special characters called via sd_event and the script, from what I remember after a certain sp level the "double quotes" are negated but there is no mention of it... Dont quote me, but that MAY be the issue you are having because the script is then incorrect...