create row on google spreatsheet via xml request

I have just completed similar project here at freelancer. google way to deal with it is to handle via Google Apps Script that is then published as a webapp. basically it will be URL that you call with an xml file and it does the job. I will need sample Sheet, rules what from xml should go to which column. I am here for less than 2 weeks, but plenty of positive reviews and 100% completion rate. repeat customers are also there...