Running Guild Wars off a portable USB device.

I go to college, and I usually get up to a couple hours between classes. I figured that I may as well put that time into Guild Wars. I have the game installed on a USB device that I plug into the college computers. When first installed, it runs fine. But to my annoyance, I have to uninstall and re-install the game each time I restart the computer. I figure that the problem has something to do with registry entries, and I was wondering if there was a registry package or something like it I could install so that I could play without wasting my time. Anyone know anything that might help me?

Edit: Goddamnit, I screwed up the title.

Edit 2.0: Thanks for fixing my title.

The first option that comes to mind would be using one of the programs that allow you to run multiple copies of GW at the same time, mainly becuase they edit the registry for you.

Guild Wars Multiloader
http://www.guildwarsmagic.com/