Minor bug, but noticeable. Start with the Reset patch. Switch on oscillator modulation, switch osc 3 to a square wave, and set osc 3 to low frequency. Push up the mod wheel, then pull it down.
What you will hear is that while the modulation amount goes up to an octave, the base pitch (the lower portion of the square wave) rises slightly in pitch. When you lower the mod wheel, the base pitch falls slightly. This might even be authentic, but I doubt it, as the Mini's square wave was not a positive-going square, it went above and below 0V. Even if it's authentic, it's wrong. The base pitch should remain steady when the trill starts and stops.
--Jim Aikin