JS problém s lightboxem

Zdarec machři na JS, potřeboval bych pomoct jelikož jsem na JS úplná lama a PHP umim základy. Mám lightbox klasickej a potřebuju dvě věci. První je, že když kliknu na fotku v galerie, tak se obrázek zobrazí ve 100% velikosti já bych chtěl asi tak 50% a ten druhej problém je, že mám v php galerii kterou volám následovně:


A problém je, že jak mám %URL%#foto tak nevím jak to v JS kódu zavolat, aby mi to skákalo na následující a předchozí fotku. Galerii sem našel na netu. Potřebuji tedy upravit JS neni to pro komerční využití, ale pro osobní blog.
<div class="pre"><pre>// -----------------------------------------------------------------------------------
//
// Lightbox v2.03.3
// by Lokesh Dhakar - http://www.huddletogether.com
// 5/21/06
//
// For more information on this script, visit:
// http://huddletogether.com/projects/lightbox2/
//
// Licensed under the Creative Commons Attribution 2.5 License - http://creativecommons.org/licenses/by/2.5/
//
// Credit also due to those who have helped, inspired, and made their code available to the public.
// Including: Scott Upton(uptonic.com), Peter-Paul Koch(quirksmode.com), Thomas Fuchs(mir.aculo.us), and others.
//
//
// -----------------------------------------------------------------------------------
/*

Table of Contents
-----------------
Configuration
Global Variables

Extending Built-in Objects
- Object.extend(Element)
- Array.prototype.removeDuplicates()
- Array.prototype.empty()

Lightbox Class Declaration
- initialize()
- updateImageList()
- start()
- changeImage()
- resizeImageContainer()
- showImage()
- updateDetails()
- updateNav()
- enableKeyboardNav()
- disableKeyboardNav()
- keyboardAction()
- preloadNeighborImages()
- end()

Miscellaneous Functions
- getPageScroll()
- getPageSize()
- getKey()
- listenKey()
- showSelectBoxes()
- hideSelectBoxes()
- showFlash()
- hideFlash()
- pause()
- initLightbox()

Function Calls
- addLoadEvent(initLightbox)

*/
// -----------------------------------------------------------------------------------

//
// Configuration
//
var fileLoadingImage = "images/loading.gif";
var fileBottomNavCloseImage = "images/closelabel.gif";

var overlayOpacity = 0.8; // controls transparency of shadow overlay

var animate = true; // toggles resizing animations
var resizeSpeed = 7; // controls the speed of the image resizing animations (1=slowest and 10=fastest)

var borderSize = 10; //if you adjust the padding in the CSS, you will need to update this variable

// -----------------------------------------------------------------------------------

//
// Global Variables
//
var imageArray = new Array;
var activeImage;

if(animate == true){
overlayDuration = 0.2; // shadow fade in/out duration
if(resizeSpeed > 10){ resizeSpeed = 10;}
if(resizeSpeed < 1){ resizeSpeed = 1;}
resizeDuration = (11 - resizeSpeed) * 0.15;
} else {
overlayDuration = 0;
resizeDuration = 0;
}

// -----------------------------------------------------------------------------------

//
// Additional methods for Element added by SU, Couloir
// - further additions by Lokesh Dhakar (huddletogether.com)
//
Object.extend(Element, {
getWidth: function(element) {
element = $(element);
return element.offsetWidth;
},
setWidth: function(element,w) {
element = $(element);
element.style.width = w +"px";
},
setHeight: function(element,h) {
element = $(element);
element.style.height = h +"px";
},
setTop: function(element,t) {
element = $(element);
element.style.top = t +"px";
},
setLeft: function(element,l) {
element = $(element);
element.style.left = l +"px";
},
setSrc: function(element,src) {
element = $(element);
element.src = src;
},
setHref: function(element,href) {
element = $(element);
element.href = href;
},
setInnerHTML: function(element,content) {
element = $(element);
element.innerHTML = content;
}
});

// -----------------------------------------------------------------------------------

//
// Extending built-in Array object
// - array.removeDuplicates()
// - array.empty()
//
Array.prototype.removeDuplicates = function () {
for(i = 0; i < this.length; i++){
for(j = this.length-1; j>i; j--){
if(this[i][0] == this[j][0]){
this.splice(j,1);
}
}
}
}

// -----------------------------------------------------------------------------------

Array.prototype.empty = function () {
for(i = 0; i <= this.length; i++){
this.shift();
}
}

// -----------------------------------------------------------------------------------

//
// Lightbox Class Declaration
// - initialize()
// - start()
// - changeImage()
// - resizeImageContainer()
// - showImage()
// - updateDetails()
// - updateNav()
// - enableKeyboardNav()
// - disableKeyboardNav()
// - keyboardNavAction()
// - preloadNeighborImages()
// - end()
//
// Structuring of code inspired by Scott Upton (http://www.uptonic.com/)
//
var Lightbox = Class.create();

Lightbox.prototype = {

// initialize()
// Constructor runs on completion of the DOM loading. Calls updateImageList and then
// the function inserts html at the bottom of the page which is used to display the shadow
// overlay and the image container.
//
initialize: function() {

this.updateImageList();

// Code inserts html at the bottom of the page that looks similar to this:
//
// <div id="overlay"></div>
// <div id="lightbox">
// <div id="outerImageContainer">
// <div id="imageContainer">
// <img id="lightboxImage">
// <div style="" id="hoverNav">
// <a href="#" id="prevLink"></a>
// <a href="#" id="nextLink"></a>
// </div>
// <div id="loading">
// <a href="#" id="loadingLink">
// <img src="images/loading.gif">
// </a>
// </div>
// </div>
// </div>
// <div id="imageDataContainer">
// <div id="imageData">
// <div id="imageDetails">
// <span id="caption"></span>
// <span id="numberDisplay"></span>
// </div>
// <div id="bottomNav">
// <a href="#" id="bottomNavClose">
// <img src="images/close.gif">
// </a>
// </div>
// </div>
// </div>
// </div>


var objBody = document.getElementsByTagName("body").item(0);

var objOverlay = document.createElement("div");
objOverlay.setAttribute('id','overlay');
objOverlay.style.display = 'none';
objOverlay.onclick = function() { myLightbox.end(); }
objBody.appendChild(objOverlay);

var objLightbox = document.createElement("div");
objLightbox.setAttribute('id','lightbox');
objLightbox.style.display = 'none';
objLightbox.onclick = function(e) { // close Lightbox is user clicks shadow overlay
if (!e) var e = window.event;
var clickObj = Event.element(e).id;
if ( clickObj == 'lightbox') {
myLightbox.end();
}
};
objBody.appendChild(objLightbox);

var objOuterImageContainer = document.createElement("div");
objOuterImageContainer.setAttribute('id','outerImageContainer');
objLightbox.appendChild(objOuterImageContainer);

// When Lightbox starts it will resize itself from 250 by 250 to the current image dimension.
// If animations are turned off, it will be hidden as to prevent a flicker of a
// white 250 by 250 box.
if(animate){
Element.setWidth('outerImageContainer', 250);
Element.setHeight('outerImageContainer', 250);
} else {
Element.setWidth('outerImageContainer', 1);
Element.setHeight('outerImageContainer', 1);
}

var objImageContainer = document.createElement("div");
objImageContainer.setAttribute('id','imageContainer');
objOuterImageContainer.appendChild(objImageContainer);

var objLightboxImage = document.createElement("img");
objLightboxImage.setAttribute('id','lightboxImage');
objImageContainer.appendChild(objLightboxImage);

var objHoverNav = document.createElement("div");
objHoverNav.setAttribute('id','hoverNav');
objImageContainer.appendChild(objHoverNav);

var objPrevLink = document.createElement("a");
objPrevLink.setAttribute('id','prevLink');
objPrevLink.setAttribute('href','%URL%#foto');
objHoverNav.appendChild(objPrevLink);

var objNextLink = docu