I am trying to query a current item in a library like so (image from Google)
but my options are
Current item seems to be missing
In help it states :
I am trying to create the workflow on a library so I am confused?
Any help/ pointers would be appreciated
Exactly, that's it. In a form library the Infopath form content is saved in an XML file (which is "linked" to the template for displaying the form content). Of course you can store XML files in a document library, but Nintex will not be able to query theses files with the "Query XML" action out of the box.
But you need only one additional step: Extract the absolute URL of the item into a variable and then use this variable in the "XML source" field.