Yeah, you just launch it and it shows this dialogue window and that's really it. Nothing special about it at all. Granted it may need writing access to same directory it is in.
Despite loads of stuff done lately this woefully neglected thread needs a bit more things to see I think.
So first thing here - it is basically how Edge nebula will look like from within in omicron systems where parts of it are available to traverse. Different areas will have slight offsets in terms of hue and brightness, but otherwise in systems receiving updates it'll be fairly consistent.
No, this is not how it's gonna look like in the end, but it's something I've done quick. Actually the test was to use texture clamp flag to get rid of pesky eye-gouging seams between otherwise pixel-perfect tiled images (actually it's a neat trick from my long gone unreal engine days). To that end it was a success and makes my work on omicrons starscapes a slightly less of a headache.
After a bit of a thought and asking in conspiracyn chat, here is how I'll handle new system backgrounds. I know some of you like addon packs that have different and typically higher resolution textures. Personally I like that background is slightly blurred so it doesn't detract you from objects on the foreground and generally I try to minimize overhead where possible, reusing available textures and scaling new ones to typical resolutions used in vanilla. But since original material for new system backgrounds is already in high resolution (2k or above images) and detail elements are mostly resolution-independent, so as a little optional bonus there'll be a pack for some of the new content (system backgrounds, nebula graphics, particle effects). It's not going to look different but simply better because of higher resolution textures. For example in images above I'm using two textures each 256x256 pixels but for optional high-res pack I'd use original 1024x1024 images.