Re: 12.10 LiveCD on USB?
I did this very thing a couple of days ago, and like with previous Ubuntu versions, I found the pendrivelinux.com site to be invaluable.
They provide a Universal USB Installer that will create a bootable USB stick using whatever ISO image file you point it to.
I did this with 12.10 and used it in "liveUSB" mode without problems. I also later installed from the same USB stick.
Ubuntu 16.04 Mate, Mint 17.3; MS Win 8.1, MS Win10 Pro.
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