The pvp part of the mod is where it's going to be tricky.
People can easily toggle off shaders.
Without the shaders, they can see much better then those with shaders.
In DayZ, there is grass, lots of it.
This allows for more stealthy approaches than the flat lands (excluding trees and bushes) of Blockland.
I am interested in how this will go and what you guys will eventually reach, but i have some fears that Blockland just doesn't fit well with, quite practically, a direct copy of the mechanics of DayZ.