Optimizing

Hello! Help me please. I tried to write a script according to the tutorial, but he deceived me. It seems that all the nodes are placed in the same way as in the video. Нowever, if paralelepiped that we want to change, explode and use its surfaces, then the surfaces rotate around its center of the plane anyway you need to separate somehow the upper plane, so as it was modified. I understand that you need to manipulate the upper edges, but then it is not clear how the guy did on video. There are simply no such nodes (like selecting the selected one). Basically all the embarrassment is that you only need to use the top surface. I will be very grateful if you can help me))) And if you know similar tutorials on optimizing the form, tell me, please) Thanks)

Here is the tutorial:

https://www.youtube.com/watch?v=6c32kZN19FU

This is my files:

https://drive.google.com/open?id=0BywYiIE3YL1VWldsZmFmOGwyNGM

https://drive.google.com/open?id=0BywYiIE3YL1VOUswblktcUlNU2M