Please explain how to do this I can do it in SP Designer but see no way in Nintex WF?
So I want the WF to Wait for a value to not be empty then set a field value
A common way is to use the "Wait for Item Update" action. The "Wait for" field allows a column in the list or library where the current item is located to be selected. This column's value will be the one that the following condition needs to evaluate as true against to proceed in the workflow.
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