I have searched and haven't found an issues like this - usually it's people with animated backgrounds that are black. Mines the non animated backgrounds, through Deskscape, that are black.
I have updated to the latest DX stuff, this problem happened AFTER I upgrade from Windows 8, to 8.1
If I select a dream/animated desktop in Deskscape, it shows a preview of it, and I can apply them, and they work - Desktop backgrounds, when previewing, show black, and apply as black - unless I preview a dream FIRST, then when I preview an unanimated desktop back ground, it shows some blocky pastel green stuff. Strange! I have completely re-installed everything on my computer and this problem persists.
Patrick Grisham
Bertram, Texas