Having an issue with semi-transparency on a spray

[Kamon]

Hey everyone, Kamon from the TF2 Division here. I usually make my own sprays, but this time I tried following the one on this guide.

Unfortunately, when I apply my spray on a wall, the dropshadow on it actually appears to be slightly lighter than the wall itself, rather than darker. Does anybody have any idea as to what I've done wrong? On the alpha channel, I gave the shadowing a gray of #66666, because I was pretty sure that was how I was supposed to get semi-transparency, but is that incorrect?

 

[Byakuya]

I'm sry I use PS so I cant help you with that, but you have to make sure the image file is proper to have no background. Not sure of all of them but files such as .png.

 

[Kamon]

....Uh, not sure I'm following you here. I myself use Photoshop CS2, and the files are saved as Targa files before they're changed into .vtfs through VTFEdit

 

[evicted]

I don't change mine with vtfedit, I just save to pictures, open the game, find it, and it works. Of course since most of my spray is completely transparent, the part that is really detailed looks pixelated but try it without vtfedit.