Fixed! My USB hard drive is now mounted to my Airport Extreme

After months of simply letting my hard drive woes with the Airport Extreme stew in the back of my mind and dealing with the consequences, I finally got off my duff and tried each of the suggestions people so graciously left in the comments of the post where I described said woes. I’m happy to say that I’ve managed to get it working again – and so I’ve updated the post to reflect that.