It's only purpose is to make animals less aware of you, which it does :)
I'm not sure you guys have started yet, but a 9 km2 map is MASSIVE. Your players will likely get frustrated with a world that large, as they tend to lag a lot more than smaller worlds, as well as travel time between players can be excessive. I wouldn't recommend going any larger than 4 km2. Even at 4 km2, travel times to get to other players can be as long as 15 minutes.
Plus that size is not supported, hence no help from us when issues arise.
There is alrady a suggestion for it on our tracker :)
In Eco you need to give the whole config file, just the seed won't help.
That's only possible with the latter idea of several claims in the shopping center.