From what I read and how I understand it technically yes, technically no. The rules don't specifically state it, but the tournaments are done on a 100% default, no mods WoW installed-PC provided by Blizzard or something like that, in an attempt to keep it purely skill-wins vs UI/mod advantages etc, or at least even the playing field a little. Pretty sure they wouldn't allow you to install anything extra on there let alone the time it would take to configure or if you use keyclone, it'd take too long to switch the systemids over and then switch them back post-tournament lol