To improve, I will just show you an example of the same work, after I make it.
EDIT: Here's a PSD on a simple shine. I hope you can learn from it. I merged no layers, so you can see it in it's entirety.
http://www.megaupload.com/?d=B6OQXIHF
Also, after making my final work in this size, here is how I would edit the PSD, so that it looks good in a showcase.
Also, keep in mind, I'm not really happy with the product. I would likely edit the half box severely from this point, until it looked very sophisticated.