Does anyone know how to cleverly control a DuplicateMovieClip's
"stacking-order effect" that would
effectively "smooth" the Den Ivanov landscape FLA so that it
appears more like the SWF example found at:

http://www.actionscript.org/showMovie.php?id=99

Whenever I export out (from this downloaded version of the FLA), my SWF
appears with a hard edge in the foreground (curves closest to the viewer)
and I perceive the duplicate instances to recede back (or behind) in the
z-direction -- which the provided FLA does not produce the desired
appearance like the smooth curves of the viewable example. Thanks.

To swap the depth of an instance of a movieclip, you simply do this:

movieClipIWantToMove.swapDepths("otherMovieClip"); //trading spaces!

or
movieClipIWantToMove.swapDepths(otherDepth); //where otherDepth is the level
where you want to put this MC