LauncherPro Custom Icons

[Batfan.com]

Is there a trick to adding custom icons to the dock in LauncherPro? I've tried adding a couple PNG's with transparent backgrounds and they show up with a black background, instead.

 

[Batfan.com]

Nevermind. Picasa was the cause of the issue. Used Dropbox to dl the image and its showing up fine now.