Simple Custom Scrollbar tutorial ,need help

I just wanted to say that I noticed a possible error in the “SimpleCustom Scrollbar” Tut.

This section does initially state to create “button” movie clips… however it then goes on to say that you should “Make sure” to select “Movie Clip” while converting the buttons to symbols

 
We need to convert each of these squares into button movie clips. Select one square (and its arrow) and press F8 (Modify | Convert to Symbol). From the Convert to Symbol Dialog window, select the option for Movie Clip and press OK.

I don’t know if this should make the code act funny or wat but I do know that my version does not work properly… In an effort to figure out why i discovered that I had made my buttons into MC symbols and the final version I downloaded at the end, had made the buttons into Button symbols. When I tested the final it worked fine.

So could this be why my version is not working?

Also in order to test that very theory, whats the easiest way I could convert them into button symbols withouth messing up the code?

thanx everyone,

~eff