I already have cut it back :), although you can get close to that if you max out the option settings for weather effects. I improved the routine quite a lot since those pictures where taken and before releasing.
I've now written a more comprehensive set of instructions: http://www.bansheestudios.com/forums/viewtopic.php?t=117
I've now written a more comprehensive set of instructions: http://www.bansheestudios.com/forums/viewtopic.php?t=117