You are correct about the problem of multiple outputs. It won't show in the trace.
The problem is that the current implementation does not support multiple output structures, and in our example there are two for each service (for example, "XML/wsdl.echelon.com/web_services_ns/ilon100/v4.0/wsdl/iLON100portType/Clear.call" has its "real" output, the exit "Clear_SoapOut", and also the exit "<<Header>>").
To overcome the problem, you can edit the model and delete the "<<Header>>" exit.
For example, in the model
delete the exit "<<Header>>" of "Clear.call" and the flow from it to the exit of "Clear.soap":
Regrading you other point (no header as input), if you look at the model, you will see that the "<Header>" trigger is not mandatory, so you don't have to supply any input for it.
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