The tunes with Tune Smithy as the author are the fractals - you can vary the parameters to make them into your own tunes. With just a small change the entire tune transforms completely - just as happens with fractal images. No experience of composition is needed for these.
The ones with Robert Walker as the author are my own compositions to show some of its retuning capabilities. The retuning midi player comes with many examples, all set up ready to play.