One major difference between the real and the virtual miniMg,is the way the oscillators are tunning. To be more usefull with the mouse, the oscillators are coarse tunning by semi-tone with right click, and fine tunning with left click. On the real miniMg the oscillators was tunning from about +/- one octave with one knob.
For the square, the virtual can output a totally 50% pulse square, the real miniMg not, so you have to tune the pulse width by right click on the wave form selector.