moderator.php is actually in the forumroot and in the admincp directory. The one that should be called is the one in the forum root. I have no clue where I got a link to the other (modcpdir), but this should be resolved in the latest update.
As far as the mod working, it was, of course, working, otherwise you wouldn't have seen the users and the link to edit them. Just because a link doesn't work doesn't mean the whole thing is broken