his game is like a flash Garry's Mod and kinda like fantastic contraption (but better). one of the best games of Kongregate! 4/5 because it has some things you could make better like being able to re size things after you place them.
to make things go away and not spawn you need to put all of your onenterframe crap in this: if(_visible == true){//all of your stuff that is inside the onenterframe} :MAKE sure it is in the ship class!