Actually, no. Those are cloud illustrations automagically color reduced, which err... actually make this screenshot illegal here :P
I'm really sorry!!
Were these backgrounds actually hand-pixeled by you or were they colour reduced sky images? This very much looks like a pattern dither colour reduction.
Thank you for your honesty, sending this back now :)
You could probably just submit with a plain blue background. Also, were the clouds here colour reduced perchance? :o