About people being in Blufor only.. i think thats just the way dayz works and i don't know if you can even change that without going deep inside the dayz files.
To change the weather: Download the dayz_code.pbo inside your @dayz_epoch file on your server.
In the External folder there is a file named "DynamicWeatherEffects".
I haven't done much more than to disable fog/rain simply by setting the max. fog to 0. Same for the rain.
