I'm not sure why this hasn't been addressed already. I didn't exactly do an exhaustive search for this problem, but you'd think that somebody would have said something by now.
I used unetbootin to write the xfce cd image to a usb stick, and the live installer refuses to run. The reason is that for some reason, the root fs isn't mounted at /mnt/salt/mnt/ during boot. Why the installer script would be written this way is beyond me, but it works, so I don't really care about that.
The way I remedied this situation is by creating a mount point at /mnt/salt/mnt/.
root[one]# mkdir /mnt/salt/mnt/sdb1/
root[one]# mount /dev/sdb1 /mnt/salt/mnt/sdb1
Although this only works for one specific configuration, a more universal way to go about this may be to ln root to /mnt/salt/mnt.
I hope this helps.