I discovered the Dark Mod a little under a year ago and loved it every bit as much as I did Thief when I first played the demo version of Lord Bafford's Manor. I'm not a "gamer" at all - I play this, Thief and...erm...that's it. I've already worked my way through all the missions, and while I'm waiting for more to be released, perhaps I should have a go at doing them properly, rather than my usual tactic of bashing everyone on the head until there's no guards left to worry about. A big thank you to the mission authors. Maybe I'll put together a teeny tiny one myself sometime. Don't hold your breathe, though. I have little enough spare time as it is.
It is a deeply rewarding experience making a mission. If I could give some advice. Pick a small level for your first one. Limit yourself, as most people
get a great idea, and plan all this stuff, but burn out because it's too much. It's better to make your first map smaller, and limit yourself, then detail the
bejesus out of it. When you think you've detailed it enough, show it to someone more experienced before you let it out to beta, and ask them to critique
It's great fun, and deeply satisfying. Good Luck Soth did a great video series on building The Bakers Job and Springheel also did a great series.