<<  
>>

...start by making a single square
 
  Create a couple of empty movie clips to hold the elements...
    ...first clip is used to hold all the elements in the scene:
_root.createEmptyMovieClip("drawing",1);

... I centre it on the stage so that the elements inside can use 0,0 for the screen centre
(the stage size is 600x300):
_root.drawing._x=300;
_root.drawing._y=150;

...then create a movie clip called 'sq' inside 'drawing' clip.
This clip will contain a single white square:
_root.drawing.createEmptyMovieClip("sq",1); 
 
  Draw a white filled square - size 4x4 origin in its centre
    _root.drawing.sq.beginFill(0xffffff,100);
_root.drawing.sq.moveTo(-2,-2);
_root.drawing.sq.lineTo(2,-2);
_root.drawing.sq.lineTo(2,2);
_root.drawing.sq.lineTo(-2,2);
_root.drawing.sq.lineTo(-2,-2);
_root.drawing.sq.endFill();
 

open raw text script...
paste the script into the first frame of an empty flash file (set script window to expert mode first),
The stage should be 600x300 with a dark background...