Could you give a little more detail about what you are struggling with on mod_xml_curl?
I was previously the maintainer for the mod_xml_curl documentation, so any feedback you can give on where this documentation is lacking would be appreciated.
The existing documentation isn't perfect by any means, but it should be enough to at least get you started.
Be sure to pay particular attention to the [1] and [2] sections of that page, getting mod_xml_curl set up is the easy part, writing the web application behind it is the hard part :)
Hope this helps
Cal