That's not correct! It must contain over 100mb, but not pictures, etc.
Ok...here's what you need to do. Create a folder called "Pictures". Put your images you want to upload in that folder. Nothing else. Then, put 100mb of crap on the disk. I used several .pdf files. Burn the disk. So now I have a disk with a "pictures" folder with my .jpg images in it (that's the only file they will accept) and that's all that's in that folder...and a bunch of .pdf files that total over 100mb. Then follow the instructions. It will work like a champ. But your disk must be burned correctly.
Also, there is some blurb in the instructions about having to have the original disk you used to change the splash screen if you ever want to go back to default. Kind of weird...but I didn't read it carefully either. May want to read that!