Flash - Ayuda con codigo actionscript

<B>Buenas tardes a todos estoy estudiando un codigo q recientemente consegui en internet... sin embargo no consigo entender muy bien dos codigos actionscript... Podria alguno de ustedes darme una ayuda exolicandome (si se puede linea a linea) los siguientes codigos</B>

CODIGO #1
filename_list = new Array();
url_list = new Array();
description_list = new Array();
filepath = "thumbnails/";

var flashmo_xml = new XML();
flashmo_xml.ignoreWhite = true;
flashmo_xml.onLoad = function()
{
var nodes:Array = this.firstChild.childNodes;
for(var i=0;i<nodes.length;i++)
{
filename_list.push(nodes[i].attributes.filename);
url_list.push(nodes[i].attributes.url);
description_list.push(nodes[i].attributes.description);
}
}
flashmo_xml.load("flashmo_067_thumbnails.xml");

var fm_menu:ContextMenu = new ContextMenu();
fm_menu.hideBuiltInItems(); _root.menu = fm_menu;
var item:ContextMenuItem = new ContextMenuItem("Created by www.flashmo.com", flashmo);
fm_menu.customItems[0] = item;
function flashmo() { getURL("http://www.sena.com"); }

CODIGO # 2

tn_group.tn._visible = false;
tn_group.setMask( tn_area );
import mx.transitions.Tween;
import mx.transitions.easing.*;
var tn_spacing:Number = 5;
var total:Number = filename_list.length;
var distance_x:Number = tn_group.tn._width + tn_spacing;
var i:Number = 0;
var start_from:Number = 0;
var current:Number = 0;
fm_info.text = "";
fm_url.text = "";
fm_description.text = "";

for( ; i < total; i++ )
{
tn_group.tn.duplicateMovieClip("tn"+i, i);
tn_group["tn"+i].preloader._width = 0;
tn_group["tn"+i].tn_button._visible = false;
tn_group["tn"+i].txt = (i+1);
tn_group["tn"+i].tn_no = i;
tn_group["tn"+i]._x = i * distance_x;

tn_group["tn"+i].tn_button.onRollOver = function()
{
this._parent.tn_pic._alpha = 50;
_root.fm_url.text = url_list[this._parent.tn_no];
_root.fm_description.text = description_list[this._parent.tn_no];
}
tn_group["tn"+i].tn_button.onRollOut = function()
{
this._parent.tn_pic._alpha = 100;
_root.fm_url.text = "";
_root.fm_description.text = "";
}
tn_group["tn"+i].tn_button.onRelease = function()
{
getURL( url_list[this._parent.tn_no] );
}
}
function move_it()
{
if( total - start_from < 5 )
start_from = total - 5;
if( start_from < 5 )
start_from = 0;
position_x = start_from * distance_x - tn_area._x;
new Tween(tn_group, "_x", Strong.easeInOut, tn_group._x, - position_x, 1.2, true);
}
fm_previous.onRelease = function()
{
start_from -= 5;
move_it();
}
fm_next.onRelease = function()
{
start_from += 5;
move_it();
}

Agradezco su ayuda con respecto a esto... hasta ahora estoy dando mis primeros pasos en este mundo del flash... asi q disculparan mi ignorancia...

Gracias
Arturo