ActionScript 2.0 :: Panning Content From Left To Right (with Stop As Intervals) Then Right To Left (also With Intervals)?

panning my content from left to right (with stop as intervals) then right to left (also with intervals)

1. I created an mc (name: "content")Notice in this mc, I layout 4 sets of text (like a page) from left to right

2. I created another mc (name: "pancontent_mc")

-I added a layer for "content" and created a motion tween for it to pan from left to right

-I created a mask layer on top of "content" that will show 1 set at a time

-I created an action layer that has total of 4 stops(); on each frame where the 4 sets of text will show directly under the mask.

3. maintimeline -There's only 1 layer. I placed an instance of buttons (left/right) and an instance of "pancontent_mc"

4. actions for right button, works fine and stops on each set of text.

on (release) {
this.pancontent.play();
}

5. actions for left button - none. I havent figured this out yet.

on (release) {
this.pancontent. - something like play previous frame until stop...
}