May be it's easy but I'm not able to do this. I need to swap
two cast members clicking on an other element/button.
For example I have a room and some buttons, clicking on a
button the wallpaper of this room swaps with an other wallpaper
that is a cast member of the library. It is similiar to a simple
rollover but in rollover the element clicked swaps with another of
the library, in my case I click an element ad another changes with
library. I hope it is clear, I really need a solution!