My son and I just finished assembling the kit and followed the image on the tutorial page as close as we could. We also notice that in our kit there were two extra pieces that we did not solder on because they were not in the v1.2 kit image on your page.
Here are images from our project.
Extras
Top side of the board
Bottom side of the board
Basically the symptom is that nothing happens when the button is depressed. I used a meter to see if the button is working and the needle moves when the button is depressed so I know it's getting power. The green LED doesn't light up though. Could that be the problem?
Regards,
Jason