I was checking through some documentation today and I stumbled across the H5 Dev Guide in the InforXtreme documentation portal. I had been told that it was going to be released by the end of November in 2014 but never saw it – I was looking in the wrong place it would seem.

https://www.inforxtreme.com/esknowbase/root/DLPublic/41145/H5DevGuide_10.2.2.0.pdf

Or through the InforXtreme Portal

Search -> Browse Documentation -> M3 -> Technology -> System Foundation -> M3 UI Adapter -> 10.2.2.0

Enjoy!