Can I get any suggestion on this request.
Unfortunately, the number of XML users on this forum is pretty tiny. I don't think any of the regular contributors use XML in their workflow, or teach it. You'll just have to wait and see.
I personally don't work with XML in InDesign too much.
This link should help you :- http://help.adobe.com/en_US/indesign/cs/using/WS372C59DB-BD13-4806-A399-794E754FF37Aa.html
look under About DTD file section.