Pressing the little down-arrow besides Demo makes a list of letters pop-up, each of these letters corresponds to a 4 step-sequence. Selecting a letter creates the 3D graphics of this sequence, the only difference to Randomize is that you know how to call this particular sequence. You could use this to select a letter (say, letter O), figure out what happened and then ask a friend to try and solve letter O as well.
Test has a similar effect, but it uses number (1 to 24) to bring up a 4 step sequences. Unlike randomize and Demo, however, you cannot use undo to go back and get a step-by-step explanation of the sequence - you need to figure out what happened by only looking at the end result! Test could be used in a homework assignment or quiz (there is no correspondence between the the demo letters and the test numbers).
And now you already know everything about how to drive the Geo-Time-Machine! Try some of the Demo letters and don’t forget to use rotate, zoom, and transparency/stripes/solid. Once you’re done press the Quit button to exit the application.