[NTG-context] Interactive things and exact placement of graphics

Hi, I have some questions again. :-) I want to draw a figure with metafun and place this on an exact place like x=3cm,y=4cm. This figure will be build of some figures which I draw with Metafun. In which way I do this? Whith layers? How should it looks like? Get some small layer with only one figure together in a big layer? And when I've build this graphic I want to put text into it and the whole graphic should be interactive. I want to lay a hyperlink over this to the web or another page in my document. Is this possible and in which way? thx jessica