What OS are you using?
What is the URL for the Document? I work with that stuff all the time.
If Open Office doesn’t have an XML import facility then you have some other options.
Download some free tool that can present it in a usable fashion.
Display it in your browser then copy / paste from your browser into some row/column oriented spreadsheet.
Bring it in as it is and do search / replace but that could get ugly.
XML Documents can get pretty darn complicated without the proper tools to parse it.
Apple OS X
File downloaded to PC
Just tried Serna. It had trouble