Problems with Fedora 18 alpha release. (Usb)

view story

http://forums.fedoraforum.org – Hello i started to use Fedora some weeks ago and i really liked it, so i decided to try fedora 18 alpha on a usb. I downloaded Unetbootin with Yum and seemed to work fine then i burned the iso with no problems, said it was finished so i proceeded to reboot my system to find that i can't start fedora it says to me missing operating system. I don't know if the new release can work on a usb or im doing something wrong. So im asking if it's possible to run Fedora 18 with a usb or i need to use another program to burn the iso image. My operating system is fedora 17. Thanks. (HowTos)