I'm having the same issue. The game freezes abruptly, no warning or problems beforehand, floating around in my skimmer in phase 2 of the treasure hunt and then locked. The music is still playing, and the rest of the computer is still there; I can ctrl-alt-del to open task manager, or alt tab to select other things, but I can't actually bring any of them to the foreground to use them. The still image of GW2 dominates the screen and can't be closed, forcing me to restart or sign out. I also had this problem at Tequatl a couple weeks ago and have been scared to try it again, apparently for good reason if it's the same.