The Alpha layer is not like any other photoshop layers. It's the layer that dictates the lighting patterns of EA games (at least live games) When you save your jerseys into dds files .... in the layers part ...you can see an alpha layer.
If you want to save them in png and add an alpha layer, check this out:
BTW, read crappystuff's tutorial in nba live 07 ... it is the one i'm using. It also has the alpha tutorial part in it.
Pdub Tutorial:
Here's how to add an alpha layer.
Save your image as a PNG file or a BMP so it only has one layer.
Open that file in Photoshop.
Duplicate the layer.
Desaturate the layer so it becomes grayscale.
With the selection tool, "select all" on the new layer, and copy(CTRL+C).
Hide that layer.
On the bottom layer, add a layer mask.
With that layer selected, click the channels tab(next to the layer tab).
There should be 5 channels.
The bottom one should say "Layer 1 Mask" or something similar.
Make it visible and make sure it is the selected channel.
Then paste(CTRL+V) the copied image into it.
It will look as if most of your jersey disappeared, this is normal.
Save the file as a PNG file. Import it using FSHx.
You can import PNG files with FSHx, you just have to type in the name of the PNG file, select it and import it.
The jersey will look blue because of the blue background in FSHx.
This is normal, go ahead and save your FSH, your done.