Update: I just noticed that this software uses Working Model as its Physics Engine!! Working Model (WM) is a 10 year old mechanism design software (Google for it, a free version is available for download), but it is rather cumbersome to use by inexperienced people. What these fellows have done, is to take a 'smart' PPT screen (they are avaialble at rather low rates these days), taken the output to a program, made it recognise patters like the cross and the 'O', and made it output a WM script. It would have been at most a month's work, but dear me, look at the results!
This is a case study in innovation ! If only I did not have this quiz looming gloomily over me, I'd have wanted to write a 5 page report on this :-( Probably I will, after the quiz :-)