heheh cool it sounds like you have it all working now
couple of things to note -
(dif_x/5) - this is where you set the speed of the scroll - try changing the 5 to something else and see the effect
also, click on your "sections" clip on the stage and have a look at the info panel. Make sure it is giving you the info of the center of the clip - not the top left corner or anything. Then you can just move the clip to a position you want, make a note of the x value and assign this to a button.
An initial position can be set by giving a movie clip an action like the buttons have but make it activate on movie load.
The code can easily be added to so you can set y values or alpha or whatever
Let me know if you have any probs