Next/Back Action script help to stop and start

Question

When I "removeEventListener" for img10, my last image going forward, Next no longer goes forward for 1-9 after going back. I've tried some conditional statements but I'm new to this and nothing is working. I also thought I could do what I did to stop the forward movement to the back movement, stopping at img1, but that didn't work. I'll leave the code that didn't work here with // before.
I'm also wondering if there's an easy way to have the transition of the photos dissolve from one to the next without setting up as parent-child. I've set it up with a UILoader.
Site is live (with these issues and others!) at : http://emilysperphoto.com/
next_btn.addEventListener(MouseEvent.CLICK, nextImage);
//variable is a container that holds some value...
var imageNumber:uint = 1;
function checkNumber():void
    //If the image number is = 10, then do something...
    if (imageNumber==10)
next_btn.removeEventListener(MouseEvent.CLICK, nextImage);
//else if (imageNumber<10)
//next_btn.addEventListener(MouseEvent.CLICK, nextImage);
function nextImage(evtObj:MouseEvent): void{
    //Add a number to the current value+1
    imageNumber++;
    largeImageLoader.source = "images/recent/rcnt0"+imageNumber+".jpg";
    checkNumber();
back_btn.addEventListener(MouseEvent.CLICK, backImage);
    //If the image number is = 1, then do something...
    //if (imageNumber==1)
    //back_btn.removeEventListener(MouseEvent.CLICK, backImage);
function backImage(evtObj:MouseEvent): void{
    //Subract 1 from the current value
    imageNumber--;
    largeImageLoader.source = "images/recent/rcnt0"+imageNumber+".jpg";
    //checkNumber();

Answer 1

Try this code (I did not check it functionality but the idea is there):
next_btn.addEventListener(MouseEvent.CLICK, nextImage);
//variable is a container that holds some value...
var imageNumber:uint = 1;
// parametarize number of images
var numImages:int = 10;
function addListeners():void {
     next_btn.addEventListener(MouseEvent.CLICK, nextImage);
     back_btn.addEventListener(MouseEvent.CLICK, nextImage);
function checkNumber():void
     // if imageNumber equals number of images
     // disable next click
     if (imageNumber == numImages) {
          next_btn.removeEventListener(MouseEvent.CLICK, nextImage);
     else if (imageNumber == 1) {
          // if number of images equals 1
          // disable previous button
          back_btn.removeEventListener(MouseEvent.CLICK, nextImage);         
     else {
          addListeners();
function nextImage(evtObj:MouseEvent):void
     imageNumber = evtObj.currentTarget == next_btn ? imageNumber + 1 : imageNumber - 1;
     // first check number
     checkNumber();
     // now load corresponding image
     largeImageLoader.source = "images/recent/rcnt0" + imageNumber + ".jpg";