Hi Rens / Robert,
I now appear to be stuck with a similar problem, I've downloaded the various docs from the open api site but there doesn't appear to be any clear documentation on how to initiate a call. I am able to login to the directory on the Omni and generate a call using the one click calling function which appears to call a DoMakeCall function so I know it is possible to initiate a call.
Rens were you able to make this work as I'm trying to build a similar call by name application for our Intranet.
Many thanks
Dave