1. You can get evoX skins from
http://www.wildabeast.net/.
If you have evoX set up as a dashboard, just put the skins in the "skin" folder.
If you have it on a cd, you can't change the skin after the disk has bean burned, but you can set it what you want before you burn it.
2. It's not a matter of software, it's a matter of hardware. All you need is a modchip, no need for a boot disk.