Took me some time to notice it, but as the title says, the layered grids are not serialized correctly when using this option.
Specifically, at least the Character height and max climb are reverted to defaule values (0.4) when hitting play (though some times it would stay a bit with the correct values it seems).
Hi
Thanks for reporting this bug!
I have in my dev version actually written a tiny json serializer and deserializer to replace the JsonFx library. It should make the ASTAR_NO_JSON compiler directive unnecessary. If you are developing for windows phone or some other platform that previously required it, I can send you a bleeding edge build so that you can try it out.