Scrolling layer won't stop where it should

can you fix this bug?

[pelachrum]

here's a piece of code I found on MM Exchange site thanks to good people who posted it there, I'm trying to tweak it to my needs, perhaps you can help

Scrolling works fine, the only thing I'm concerned about is it:
1. initialy loads the scrolling layer inside the container in a wrong place
2. scrolls too far to right; does not stop where the scrolling layer ends
3. scrolls too far to the left; does not stop where the scrolling layer starts

few notes:
the container layer is the one with red background, scrolling layer is yellow and it has text in it so that you can see the effect I'm looking for.

I uploaded a sample image of what the layers should look like upon loading the page and when it's scrolled all the way to the left
[pawelcreative.com...]
... and when its scrolled to the right
[pawelcreative.com...]

in essence the container layer (its background color in this case) should never be visible

finally here's the link to the page and its code in question [pawelcreative.com...]

let me know if any of this is unclear

anybody has a solution, your help is much appreciated
thanks

[webjunk]

clip: rect(0, 200, 500,0);

Tweaking this coordinates probably will give you correct results. Just an off hand comment seeing the code. I got to hurry since this is weekend. ;)