Need advice for Fn key usage in Motion.

I am just beginning my usage of Motion 4 and working through Mark Spencer's book. The book keeps referring you to use the Fn keys. But mine don't work the way they are supposed to. I went into System prefs and selected the use all Fn keys and when I go back into the program to use them I press the fn key and the appropriate Fn key (ex. F5 to open the project pane) and all I get is a beep and nothing happens. If I just use the F-F8 procedure it will just add an f or a 5 etc, into the area at the bottom for the current time. Or if I hit the Fn-F8 it opens iTunes. I know I can work it out by using the long way around. But I know it is easier to use the function keys from experience in the CS4 suites. Is there anything I am not trying or something anyone can recommend to make these work properly?

Thanks,
Scott