This means something is null . This is such a duplicate question. At least 50 questions like this are answered.
Please learn what the error means and how to fix it at http://curtismorley.com/2007/08/15/flash-cs3-flex-error-1009-cannot-access-a-property-or-method-of-a-null-object-reference and maybe google a bit for debugging as3. Its more helpful, if you understand, than asking others to fix your code. Also, at this error the stack trace (and the line the error is on) is very important, because something is null there.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.