Is is seamless in the corners? If so, is it some huge ass image that will take forever to download?
It's 100% seamless and is actually 5 different 512x512 .jpg images (Six of them if you include the bottom). From my knowledge you can't download skyboxes from a server and have to have the map that uses it to see it.
is there a tutorial on making this?
Yes, this one is to create a skybox with
Terragen 2. It doesn't tell you how to use Terragen 2 though.
You can also use
Terragen Classic, which is way easier to use but it' not as HQ.
North-East-South-West, they aren't seamless because I took the pictures from in-game.



