Main problem that I can't just emit particles from random point in space (e.g somewhere in sky), there need to be unit which activate effect. As you might see on screenshot I just replaced nanolathing effect of delta commander with modified fab spray. Also I don't get it yet if there some other event, so unit can run effect while moving.
Love it SXX!! the first couple of pictures was what I was getting at. Snow1 and Snow2.jpgs I think would be better not showing as big snowflakes as that put you hit the idea perfectly, snow3 and snow4.jpg perfect!! and you even made a tornado for it haha... brilliant man!