2921662 - How to capture, replay and save an erroneous request as a test case in Gateway Client for debugging?

How to capture, replay and save an erroneous request as a test case in Gateway Client (/n/IWFND/GW_CLIENT) for debugging with Traces (/n/IWFND/TRACES) or with Error Log (/n/IWFND/ERROR_LOG)?

If this KBA was sent in an case then open R3 Connection to the Gateway front-end (Hub) system and to the Gateway back-end system too (if any),
AND maintain the same user in both the front-end and the back-end for the processor of the case (the back-end user must have S_RFCACL authorization object for testing).

SAP Gateway (SAP_GWFND)

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