You can't "call" an XML file. XML is a data description language, it doesn't define imperative code to be run. That'd be like, for instance, running an INI file. Can't do it, nothing to run.
What you need to do is find an XML library so your BlitzPlus code can read XML files and decide what to do with what they contain.
What you need to do is find an XML library so your BlitzPlus code can read XML files and decide what to do with what they contain.