How do I make a timer?

you know when we play some games and we try to unlock chests, there's a cooldown timer right?
so we close the game for a while, and when we get back the cooldown has ended?
even if we didn't run the app?
how do i implement a similar logic to stencyl?

please respond i am losing confidence of ever completing my game..

There's an extension to help with this kind of thing - http://community.stencyl.com/index.php/topic,15063.0.html

I've only briefly used it myself, but it's pretty easy to get to grips with.

oh my god thanks for this!!! finally i can start making my game! thanks a bunch!