I've tried with two different USB sticks, three different .iso images, and on
two different machines running Trisquel 6.
Each time, the following error:
An uncaught exception was raised:
Invalid version string 'GNU/Linux'
Looks like it's an ubuntu bug:
https://bugs.launchpad.net/ubuntu/+source/usb-creator/+bug/1068332
http://askubuntu.com/questions/173615/an-uncaught-exception-was-raisedinvalid-version-string-gnu-linux-when-creat
http://askubuntu.com/questions/162760/startup-disk-creator-uncaught-exception-error
[the fix suggested here did not work for me]
SHould I install unetbootin, or is there another way?