How can I install Ubuntu from USB stick on a UEFI-based x86-64 system? Documentation for this topic doesn't look very friendly.
Did you take a look at the threads at ubuntuforum.org?
For example: http://ubuntuforums.org/showthread.php?t=2015019
There is also answers here on Ask Ubuntu for previous versions of Ubuntu: How to boot Ubuntu from EFI/UEFI?
Not that I know anything about this topic, I just did a google search for you.