Today, there is no way to return a 'warning' state, though it can be logged. The Get-WfaLogger cmdlet can have a -Warning flag set which will return a message into the wfa.log and report to the workflow_execution.log. Other than this, it might be work requesting an RFE. The challenge will be in handling the exit code to trip the Error vs. Warning state.
Jeremy Goodrum, NetApp
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