Is the logic screen supposed to show the default Yosemite wallpaper or your current wallpaper? I seem to recall that it would show any wallpaper blurred out, but now it only shows the default Yosemite wallpaper.
Hi, I had the same problem with the wallpaper defaulting to the yosemite image. To fix it place the images you want to use it the apple default folder. The one that has their images in. I haven't had the problem since I did this.
Cheers
Peter345