Thanks for your reply. I don't know how but I did overcome the above issue but it happened again later in the tutorial (in part 5-6) with the Database/Update.
Drag & drop of the Requisition element - as you suggested - overcame the problem.
I did notice that the property in the trigger is named "dataTypeId" whereas in Requisition and Update it's named "refId". Not sure if that is relevant.
As I work through the remainder I'll pay close attention to the Properties to see where I'm going wrong.
Thanks again for the solution.
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