Just to provide a little more detail on my post. You reference the webservices/assembly/WCF service via the 'References' icon on the K2 Studio ribbon when you have a process open. Alternatively you can use the Ctrl-R shortcut key. Once you've pointed it at your external reference, you can then drag out the Reference Event from the 'Event Wizards' tool box. You'll then be prompted to configure this event. This wizard permits you to leverage true objects, much like if you were writing code. By that I mean, you can load an object, get/set properties and make multiple calls to various object methods all within a single event. As such you will be prompted to select a constructor for your reference (you'll be presented with a list of available process references to choose from). Once the constructor is selected and configured you can then add in the desired method(s). Again this constructor and method config is all done within a single References Event wizard.
HTH.
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