FMX04 duplicatemovieclip help please

I am very rusty and could do with some help I am using MX04 and am using some of the XML flash tutorial from this site(but cut down to what I need)
The code is below and works with createEmptyMovieClip but I would like to get it using duplicateMovieclip so I have a bit more control of the place holder. I havent used this looping for a long while so am extremely rusty. I pretty much get all thats written below and have played around with the duplicateMovieClip but just cant get it into the duplicated movies (or see them for that matter) but they are there in the “list variables”
The code below is used on this page so I know its working.
I would really appreciate any help on my first post to this forum.

function GeneratePortfolio(portfolio_xml){
var portfolioPictures = portfolio_xml.firstChild.childNodes;
for (var i = 0; i < portfolioPictures.length; i++){
var currentPicture = portfolioPictures*;
var currentImage_mc = _root.image_holder.createEmptyMovieClip(“image_mc”+i,i);
currentImage_mc._x = i * thumb_spacing;
currentImage_mc.title = currentPicture.attributes.title;