Brian,
each style has the two usual variations, and each variation sounds different if you play a major, minor or seventh chord. Furthermore, there is a function called "interactive arranger", which activates more or less rhytmic tracks depending on the melodic line you play with your right hand. What is really interesting is the possibility to sync to the rhytm section an audio loop (even sampled by you). This loop will be stored (as a .wav file) on the hard disk and will be loaded automatically each time you select that style. So I would say that the possibilities are endless...
The CD contains 16 short songs composed on the SD1, without external instruments or effects. Eight of them can be found at http://www.ketronclub.it (there are links to the Solton clubs of USA and Germany). Maybe if you ask them they will send you a copy; they were really kind (there was even a cocktail party before the demo) and I have to agree with DanO: Sandro Fontanella is really a nice person and an accomplished player.