Remove attached movieclip in reverse order of placement

Perhaps using an array to store the movie clips names that are attached would work. Then you could use the array.pop() method to get the last element entered and remove it from the array at the same time.

I bolded the lines I changed/added in your code.

var i:Number = 0;

var dotArrays = new Array();

this.onMouseDown = function(){
var drawdot:MovieClip;

drawdot = this.attachMovie("dot", "dot_mc" + i, this.getNextHighestDepth(), {_x:_xmouse, _y:_ymouse});

dotArrays.push(this["dot_mc" + i]._name);

var nextdepth = this.getNextHighestDepth();
trace (nextdepth);
}

clear_btn.onPress = function() {

var delete_mc = dotArrays.pop();

removeMovieClip(delete_mc);

}
}

Let me know if this works ok.

Sorry! I forgot a line.

After: dotArrays.push(this["dot_mc" + i]._name);

Add: i++;

Yay!  Your welcome.