Thanks to EVERYONE 
In a very short time, I have managed to transfer an entire multi boiler / zoned heating system from one platform to openHAB2.
It took me weeks and weeks (and a lot of money) to get the first system up and running, so for it to fail was heartbreaking.
I put openHAB2 in for them, as I thought they would be able to cope with a change of layout.
It turned out that I was wrong, so I have had to recreate the “old” layout in openHAB2.
Thanks to InkScape, SVG and your help with the coding, they now have this..
For all three areas of their building.
(the brief was “Chips or Mash?”, no bells or whistles, just keep it simple)
If anyone is interested, I have zipped up the Things, Items, Rules, floorplan.css and SVG files here
There is even a Lockout for each day, so if the Second ON time is before the First OFF time, the First OFF is ignored.
It works when the Things, Items and Rules files are loaded, which were inspired by this Thread.