Yoyo Games FPS tutorial?

Hi I have game maker 8 pro and I downloaded the fps tutorial on yoyogames.com . The game works great but i want to put a menu at the start so you can click on start and it would move to the next room. I added the backround and a START object. When I play and click on START it comes up with a error. Can someone who has the tutorial please help me add a menu.