Just to say I am looking into the mapping and have started some bits, which I will share in the near future, but just to say don't underestimate how big a task this is.
There are 5,000+ locations inscribed at the moment. There are some shortcuts we can take but on the whole it is fairly long trek, and with some exceptions it isn't something that is too easy to collaborate on without some (free but) specialist software, so is a little different to the work we have conducted previously on mapping locations.
Mapping the core zones is the focus, when looking at the data it is the most logical next step, however it can be done in parallel with any potential POI work. We already have a source for the core zone data for majority of the natural and mixed sites and I have the ones for the UK and imminently the Czech Republic. But if people are aware of local agencies that hold the data for this please feel free to flag them up, I will start a thread.
I'm still trying to decide on the value of buffer zones, I understand that all data is valuable, however it would well double the time required to do it, which is already measurable in multiple years rather than days or weeks.
Further details will follow in the next few weeks but just to let you know there is some activity on it.