Decode/Encode .swf file - actionscript-3

Question

I have this .swf file: http://www.mediafire.com/download/hrr3c6c188jsgvd/upload.swf
I need to change something in this file, so I have this website http://www.showmycode.com/ decode the file and got those code:
if (!hasOwnProperty("_load05626E90")) {
_load05626E90 = true;
telltarget ("..") {
var copyright = function () {
telltarget ("..") {
geturl("http://www.google.com/search?q=PHP+Script+c-Image+Uploader+3.0", "_blank");
}
};
}
}
else {
// unexpected jump
}
var author = function () {
telltarget ("..") {
geturl("http://chiplove.biz", "_blank");
}
};
// unexpected jump
// unexpected jump
var uploadItem = function (num) {
telltarget ("..") {
var item = flash.net.FileReference(list[num]);
item.addlistener(listener2);
item.upload((((((((((("upload.php?watermark=" + watermark) + "&logo=") + logo) + "&resize=") + resize) + "&server=") + server) + "&q=") + q)+ "&account=") + account)+ "&password=") + password);
}
};
// unexpected jump
// unexpected jump
var FileChooser = function () {
telltarget ("..") {
var fileRef = new flash.net.FileReferenceList();
fileRef.addlistener(listener);
fileRef.browse(allTypes);
}
};
// unexpected jump
// unexpected jump
};
stop();
//---------------------------------------------------------------------- //Frame 1 //----------------------------------------------------------------------
this.menu = new contextmenu();
this.menu.hidebuiltinitems();
this.menu.customitems.push(new contextmenuitem("PHP Script - c-Image Uploader 3.0", copyright));
this.menu.customitems.push(new contextmenuitem("Powered by chiplove.9xpro", author));
//---------------------------------------------------------------------- //Symbol 3 Button //----------------------------------------------------------------------
on (press) {
var listener = new object();
var listener2 = new object();
var itemnum = 0;
var numfiles = 0;
delete _global.__resolve;
_global.__resolve = _global.__debugResolve;
if (list == undefined) {
var list = null;
}
var allTypes = new array();
var imageTypes = new object();
imageTypes.description = "Images (*.jpg; *.jpeg; *.jpe; *.gif; *.png;)";
imageTypes.extension = "*.jpg; *.JPG; *.jpeg; *.jpe; *.gif; *.png;";
allTypes.push(imageTypes);
listener.onselect = function (fileRefList) {
list = fileRefList.fileList; numfiles = list.length;
uploadItem(itemnum);
};
listener2.onOpen = function (file) { };
listener2.onProgress = function (file, bytesloaded, bytestotal) {
flash.external.ExternalInterface.call("loading");
};
listener2.onComplete = function (file) { };
listener2.onUploadCompleteData = function (file, data) {
var loadvars = new loadvars();
loadvars.decode(data);
flash.external.ExternalInterface.call("displaypic", file.name, loadvars.image);
itemnum = itemnum + 1;
if (itemnum < numfiles) {
uploadItem(itemnum);
}
else {
flash.external.ExternalInterface.call("responseStatus", "Done!");
}
};
flash.external.ExternalInterface.addCallBack("FileChooser", this, FileChooser);
flash.external.ExternalInterface.call("clearlist");
FileChooser();
}
I think this is Action Script code, so after make some little change I get flash builder to recompile it, however, flash builder show a lot of red underline (syntax error) in my code and can't build those code to .swf file again. I wonder if the code I got from showmycode.com is correct, or is it action script? If the code I got from showmycode.com is not correct, how can I decode, edit, then encode again that "upload.swf" file?