Questions about some features?

First off, great program although I'm a little limited right now. In the video "VerveDemo01" Taron used his 4 brush to make foliage on the foreground. His brush looked biased from both sides at clean cut angle but when I bias mine it does so in waning moon. And also his brush kind was "randomized" which he said in the video but I don't see an option for that. I would randomize it myself but whe never I try to use a biased brush, for some reason it keeps spinning and just turns it into a hollow circle. I'm using windows 8 and no draw pad if that matters. I can provide anymore info if necessary. Thanks in advance. 
