Is there any kind of job in Nprinting which connects to Drupal via an API
Are you trying to initiate a Nprinting job from Dupral or write output from Nprinting to Dupral?
I am not an OEM provider, but I am reasonably sure that you have to either be in Nprinting or initiate an Nprinting job through Qlikview for it to execute.
You can initiate NPrinting tasks from an XML file.
How to Execute NPrinting Reports by External XML Request
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