Transforming Open XML Documents using XSLT 
(Eric White) Transforming Open XML documents using XSLT is an interesting scenario. However, Open XML documents are stored using the Open Packaging Convention (OPC), which are essentially ZIP files that contain XML and binary parts. XLST processors cant open and transform such files. But if we first convert this document to a different format, the Flat OPC format, we can then transform the document using XSLT. Perhaps the most compelling reason to use XSLT on Open XML documents is document generation. You can take a source template Open XML document and source XML data document, and produce a finished, formatted Open XML document with content derived from the source XML data document.
Read More >>