AS2 to AS3?

[Flyingcow]

for Key.isDown, see this post

http://board.flashkit.com/board/showthread.php?t=798096

as for the mouse/EnterFrame events, look up addEventListener in the documentation.

basically you do

objectThatListens.addEventListener(EventName, functionToRun, false, 0, true)

The extra parameters are an extra precaution for memory leaks when you remove the listener.

public function functionToRun(e:Event){
...
}

replace e:Event with the type of Event you are listening for. All of this is listed in the documentation.