Only problem with this script is that if the user is already set to an instance, such as an adventure dungeon, this will overwrite it. One way around that, which I've setup on my server, is to add a new command that allows you to save your current instance flag before going into the guild hall.

(Oh, and hi Aergad)

What I mean by that is, if they are flagged for another instance, but not in it at the moment. Say they are flagged for some adventure zone, but they haven't gone in yet. If you enter the guild hall by this method, it will overwrite their other instance flag.