[NTG-context] mouseover ... (again)

Hi Hans, Patrick et al. I really would like to learn about mouseover and other PDF related ConTeXt features (probably JavaScript related). In an older email Hans told Patrick that he'll send him a nondocumented example file - so does this mean that there are no other example files available? Please, if some of you could give me some readable read (as .tex files) examples on how how to work with buttons, mouseovers and other interactive PDF elements like this, I would be very happy! Thank you very much, Steffen