GUI is coming in 16. I may have to put my 6a on the beta to play with it. As of now I don't think there's is a way to use anything other than Debian, but I'm sure some tools will pop up once it's less experimental. Reading the docs it looks like you just need a kernel, initrd and a disk image to hand to the VM, but I didn't think there's a front end for that yet. It just came out in the March update, so it will take a bit maybe. 16 should be out by summer, will probably see more tools then.