Hi everyone, I'm not sure if this should be posted here, or on the custom background thread, so please feel free to move it, if it is in the wrong location.
Here is a background I've put in, that seems to work really well. It is already in 2048 x 1024, and makes the game have kind of a "relaxed" feel to it, even when there are intense things going on. The picture is of some clouds, and I don't see any lines, or weird stuff when I play it, so I thought I'd upload a few pictures and the .png file if anyone wants it. All you need to do is move it into the Steam>steamapps>common>audiosurf>engine>textures folder, and make 3 copies of it, named Skysphere_Grey, Skysphere_Black, and Skysphere_White. Then it may take a few seconds to load, but once loaded, there seems to be no delay for me.
Thanks, Mapsking
:Edit: The .PNG file is too big to upload, so it can be downloaded from here:
http://i451.photobucket.com/albums/qq238/mapsking/Clouds.png