Can't execute function to show invisible button

I am trying to create a section of a program in which the user will have to go to all areas before they can move onto the next section of the program. With the help of someone on a different forum, I was able to modify the following code to try to make this work.

I can’t seem to finish this off. The code is logical and I believe that this should work - but it doesn’t. If someone could please help me find my “stupid” error, I would appreciate it. I saved the .fla as a F8 document. Thanks a lot.