Quite tough going, because it's a pretty, sophisticated piece of code that does a lot of things (much squinting and lots of peppermint tea was involved in the study thereof). My little opus sort of worked, for some values of sort of. That is, it compiled and I learned a lot.
But it was a bit of a woolly ball because much of what is in ooxml/word doesn't really apply to odf, so, Peter rescued me and helpfully made a great starting structure for me in this patch:
So, more peppermint tea, some good hacking music and I'm all set to code this thing ;-)