Symptoms

Having an issue with the "Create Reference Event" in a K2 workflow, that is being called by a K2 for SharePoint workflow. The hand-off between the workflows is fine, and the data field that is used between the 2 correctly sends the data, but the activity for "Create Reference Event" fails. In the workspace we see the generic error of "Object reference not set to an instance of an object.". I tried using a static value to rule out the data field and the error appears even when manually entering the value into the workflow. The error in the Event Viewer is:

28083 ServerEvent: Object reference not set to an instance of an object.
InnerException: Exception has been thrown by the target of an invocation.
InnerException: Object reference not set to an instance of an object.
 

Diagnoses

This is a bug in the product whereby the IPC event does not properly map the "Item Reference" reference from the parent process at runtime.
 

Resolution

This will be fully addressed in a future update.
In the meantime, a workaround is to create the EXACT same item reference(with exact reference name) in the parent Process and child(IPC) process.