I just finished installing Xubuntu 13.10 in UEFI mode. So it's a fresh install.
However, I am not logged in. I am currently up and running with the USB flash drive I used to install it, since I can't use my keyboard and mouse at the login screen.
They are connected via USB ports and wired. I did not have any problems at all using them during the installation process and never have problems using them clicking and navigating around in the UEFI menu right after bootup.
(FWIW, this particular thread was not really a solution to the problem imho as I would like to stay with Xubuntu and not use another distribution.)