do not install any themes from
http://www.themes2wp.com/
i just finished cleaning up a clients wordpress multisite, pain in the ass, each theme when activated, adds nasty code to your themes functions file, not just the activated one, but it cycles through every theme you have in your wordpress folder, so even if you remove the code from one, once you activate another theme it will repeat the process over and over.
just a tip, when downloading any theme, check the header footer and functions file for anything nasty.
hope this saves some people from headaches.