It may be of note that under Vista the program files folder is a restricted folder that only system and admina ccounts are supposed to access. Writting to the program files\glest folder is not the reccomended action, and since there is a linux port, there's no reason why glest would have to anyway when the problem has already been solved for linux users.
Duckman, for the moment I can only think fo either installing glest to the public/shared docs folder, or using the run as admin setup so glest always runs as the same user, but that would probably mean you have to type in user passwords eachtime it ran.