That file describes the format, rather than the content, of an XML-RPC request and its response, i.e. it's a kind of meta-file.

The "CreateNDTicket" thing is just a wrapper around the description of both the request and the response which identifies it by name.

So what you've got is a file which says "'CreateNDTicket' is an RPC request, it will send the following kinds of data as a request, and it expects the following kinds of data as the response."

So, what do you actually need to know -- how to send one of those requests? What to do with the response?

It's nothing to do with style sheets or XSL as far as I can see.