Help with script to translate randomly-placed layer into specific coordinates.

Question

I have a set of images in a folder. They all have the same size (200px x 200px).
I create a large blank document, and I'm making a script to put all the images in my large document as a series of layers.
The idea is to make image1 align with the left edge of the document, and then have the rest of images follow to the right (imageX is X*250 pixels away from the left edge of the document). That way I would get a series of images that start at the left edge and go right, separated by 50 pixels from each other.
My code is something like this:
var folderPath=Folder("C:/bleh/images/");
var images=10;
var imagesWidth=200;
var separation=10
var newFileName;
for(var i=0;i<images;i++){
     newFileName="image"+counter+".jpg"
     app.load(File(folderPath+"/"+newFileName));     //open the new image
     backFile=app.activeDocument;
     backFile.selection.selectAll();                 //select it's contents
     backFile.selection.copy();                      //copy them
     backFile.close(SaveOptions.DONOTSAVECHANGES);   //close the image
     app.activeDocument.paste();                     //paste the image's contents into the large document
     app.activeDocument.layers[0].translate(20,0)    // <---- THIS IS THE PROBLEM
The problem is that when an image is pasted onto the large document, it seems that it aligns itself depending on the current view's zoom and seeing area. That means that each time the script is ran, the images will be pasted at different "global coordinates". This is a problem because the only way to move a layer seems to be with the layer.translate() function, which takes as parameters an amount in pixels to move the layer. I can't find anything that remotely looks like "align layer to the leftmost edge" or anything.
I want to be able to translate them all the way to the left (and then translate them again in this manner: deltaX = i*(imagesWidth+separation)).
So how can I find the gap in pixels between the left edge of the document and the edge of the layer/center of the layer?

Answer 1

Here is the align method..
align("AdRg");   // move layer to the bottom
function align(method) {
activeDocument.selection.selectAll();
   // methods:
   // 'AdCH' - center horizontal
   // 'AdCV' - center vertical
   // 'AdLf' - left
   // 'AdBt '- bottom
   // 'AdTp' - Top
   //  'AdRg' - Right
   var desc = new ActionDescriptor();
           var ref = new ActionReference();
           ref.putEnumerated( charIDToTypeID( "Lyr " ), charIDToTypeID( "Ordn" ), charIDToTypeID( "Trgt" ) );
       desc.putReference( charIDToTypeID( "null" ), ref );
       desc.putEnumerated( charIDToTypeID( "Usng" ), charIDToTypeID( "ADSt" ), charIDToTypeID( method ) );
    try{
   executeAction( charIDToTypeID( "Algn" ), desc, DialogModes.NO );
   }catch(e){}
   activeDocument.selection.deselect();