as2 is easier.
create a horizontal scrollbar in the authoring environment
and convert the scrolltrack and slider into movieclips with their
registration point at their left edges.
assign an onPress handler for the slider that initiates the
slider's startDrag() with parameters set to the left edge of the
slider track (0) and the right edge (slider track's _width minus
the slider's _width) and initiate a loop that repeatedly updates
your image's _x property based on the slider's _x property.
finally, assign an onRelease handler to stopDrag() and
terminate your loop.