Hi Guys, since posting details of my tool I've had a couple of interesting bits of feedback. Which in turn has made me aware of.
http://webodf.org/ - it is licensed as AGLP - not sure if that is acceptable. And https://gitlab.com/odfplugfest/odfautotests/blob/master/doc/01_introduction.md an ODF Testing framework. -- Cheers, Ian C