How to extract the HTTP response from immmediate delivery method.

I need some info on Delivering Documents with an Immediate Delivery Method.
In the partner profile,the delivery method has been set as Primary HTTP and the processing rule has been configured to deliver the document using ‘immediate delivery method’

TN transaction logs show that the document has been sent succesfully via HTTP.
In the content tab only xmldata is logged.I am not sure why the response part is not getting logged.
Also,how does this HTTP call return the response?
Is there a way to capture response that is obtained as part of HTTP call.

Documents delivered using Immediate Delivery Methods are Tasks in Trading networks (you can configure retries etc for that task). To view the response from the server for http delivery

Integration->B2B->Transactions
Click Details button for “Transaction Details” and choose “Task” Tab then click on Details button for Task Details and Pipeline. The Pipeline tab will have input/output for that task including server response.

How and where do i configure to update the user status of that transaction to DONE if i get a success response ?

You could change it by invoking service “wm.tn.doc:changeStatus”.