Can't get Flash buttons to work in .FLA file?

I have a school project and our teacher can’t even figure out whats wrong. We have to make a movie/mini site for our final project and we have an intro layer/scene that stops and three buttons fade in to navigate to the respective sections (forensics, web dev, and business). The forensics button goes to the forensics page and the home button brings you back to nav page, perfect. However when I try to do the exact same commands for the other two buttons it doesn’t work. Can anyone clue me in on what I am doing wrong? Its due Thursday and I am freaking out!
Here is the file…

Use a trace in your button release function to check whether the release is actually being activated. Are you putting actionscript attached to a movieclip/button, or are you putting it in the timeline and referring to an instance name to attach it? Check that the instance name is correctly assigned, and that button instances that span keyframes in the timeline retain their names or any attached actionscript.