Adding a node to Word's XML

Question

Why couldn't office use the standard System.Xml.XmlNode?

i need the ability to quickly append xml to an existing node.  how can
i do this?
What i am doing is deserializing an object and i need to make it the
child of an XmlNode.  the problem is that there are three different
XmlNode elements out there and in word/vsto, the one i MUST use is
Interop.Word.XmlNode.  It happens to be the one that doesn't have an
InnerXML or LoadXML method.  Why?????

how can i solve this problem?  i basically want to serialize my objects
as XML fragments wand add to a given node in my word document (as wordml of course).  Doing it this way should take less than 10 lines of code (and works perfectly in the typical .Net world when using System.Xml.XmlNode).  But if need to now manually create each node, name it, set it's namespace, figure out what attributes and elements i need to add...it becomes a mess and the only way to make it generic is using some crazy config files or some crazy reflection code.  But even with reflection, there is no way to guarantee the sequence of how elements are written.

please help!

(and microsoft...for the love of God...move towards the standard .Net
System.Xml package!)