Anatomy quizz

Hi,

I want to copy the very same principle that ‘poke-a-muscle’ and to make much more levels BUT I don’t know how to make a countdown, how to use it to add the leftover of each countdown to create a score, how to create a mask linked with the mouse to ‘scan’ the body and how to insert an animation of the texture inside the game(sothat the muscle to pick would start changing colour to help)

Please comment and help