An update before the main review - the Mac version does not have 3D flyby view (which is a shame as it's a lovely feature of the Windows version) - VP Maps take the view it will be "...some time away." They said, when I asked, that "...it was not considered a hugely important module for first release, and with this a totally new application, we have a plan to build features in the longer term." Fair enough and very honest of them, we'll await developments, but I would have liked to have seen it straight away. I accept, in the round, there are more important features.
Also, the Snowdonia NP bundle does not seem to have waypoint height data but, if you download the Wales Anquet Free Height data in the My Maps section of the Map Manager it will translate to the waypoints on the Snowdonia NP map. Many thanks to VP Maps for extremely quick and courteous responses.