When I run the sketch with Processing 2.0.8 and the most recent Minim jar files from Github, it works for me. I get some errors about controlP5 (the GUI library used here) not being compatible, but it doesn't stop the sketch from running. One thing is, you should not be including UGen.java in your sketch because it will likely conflict with the version in minim.jar. So, I'd recommend removing that file from your sketch, making sure you've got the library installed properly (though I expect the version that is currently shipping with 2.0.8 will also work). Try running it again, if it still doesn't work, post the error here.