The older 3.0.2 source should still be viable thru 14.04 as most of the deps are available for 14.04. However better to rebuild & package for trusty as an upgrade to current gnome-disk-utility package, so to that end a ppa.
Uses the last 3.0.2 source in Ubuntu - 3.0.2-2ubuntu7 precise (- the package name inadvertently got 8 at end, no matter really.
Only real change was to remove nautilus extension & launchpad integration as no longer working or used & would cause a ftbfs.
The default opening window size is a bit small, needs to be resized or maxed after opening. If I stumble upon a way to adjust in source will do so. ( patch welcome.
If unsuitable then either use ppa-purge or just remove ppa, remove gnome-disk-utility, update sources & re-install current gnome-disk-utility.
Copied over a previous build to ppa for saucy (saucy is almost EOL
As far as usb creator, the 14.04 version is fine, just format the flash drive first to fat32, then open usb creator and it should work ok.