I don't know the technicals about it, or what program you made it with, but when I opened the image in Photoshop, it is actually an 8-bit bitmap, with 11 colors. It needs to be saved as 4-bit with 16 colors.
When saving it (in Photoshop), you want to choose "Perceptual" for the palette, not "Exact."
Also, the size is wrong. Your image is 642 x 842, and your Progress Bar is 21 x 9, not 22 x 9.
Oh...one more thing...you spelled "Edition" incorrectly - you spelled it Edtioin.
One more thing -- save yourself some frustration and download RabidRabbit's Bootskin Buddy here: http://hypknotic.deviantart.com/art/BootSkin-Buddy-30733603
It's a little program that puts it all together for you, won't work if there is something messed up about the images, so you'll know before trying to upload that it's not going to work and will get rejected, without having to wait for it to go through moderation to start scratching your head on what's wrong.
