Hey Highwayman,
I know this doesn't help the mission download issue of yours, but that mission you want to download is pretty easy to setup yourself within the mission editor. Give me a PM and I'll walk you through it. I know it doesn't solve the issue at hand, but at least you'll be able to practice some AAR. Cheers to you on that as well. It's tough and frustrating but ultimately (in my opinion) the most satisfying part of the game.