erez -- Put the current shipping option name in change shipping from and then put "Cheapest" in change shipping to. It must match exactly, so if it doesn't work I'd check your database and grab the shipping name directly from the database. Its quite possible that there is some html code in the shipping name.
mahoneys -- Version 5 should be able to create the XML file using the text file attachment feature. However, this will not send it to an FTP site, it will only attach it to an email PO.
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