This looks like you are trying to insert XML within an XML structure (possibly within a tMap?). The problem you have here is that the tMap will interpret the String XML you are creating as a String. It is quite rightly escaping the content so that it will not break the XML structure you are inserting it into.
What you can do to get round this is to put a value to replace (maybe something like "**REPLACE**") into the XML field where you want to insert the XML you are writing as a String. Once the main XML is built, use a tConvertType component to convert the XML Document to a String. Then use String replace functionality to replace the "**REPLACE**" value with your String XML. The (after removing the XML Header) use a tConvertType component to convert the modified String XML to an XML Document.
It is a bit fiddly, but works quite effectively if you want to add XML sections to an existing XML document.
