First thing I noticed is you have every button set to open in a new window (or tab) Since it does that, there IS
no page to go back to.
You need to set the links to open in the same window (or tab).
Why do you use Flash buttons? Flash buttons are not web accessible. And people who can't use Flash on their web devices (iPhone, iTouch and iPad users for example) won't see anything.
History Links with plain buttons.
Note: History links don't work if the browser's History Folder is empty. Don't use this on pop-up or target="_blank" pages.
Do I add this code to the Dreamweaver pages or the Flash Buttons?
To answer your other question about Flash buttons. I honestly don't remember why I made Flash buttons? I know I didn't like what DW offered for buttons. I used Spry in the past but had a terrible time keeping the buttons consistent.
My biggest issue is I live in Alaska and don't have someone to bounce ideas off. What do you use for navigation buttons?