Wow, you guys can't be serious. You can clearly see shadows on the wall under that alcove. It doesn't look fullbright at all, it just looks overly bright and possibly misdirected. I bet he left the angles all at their default values, which would make everything really bland like it is. I'm kind of baffled by his brightness setting though. It looks to me more like 80 or 100, definitely not 2.
As was mentioned before, make sure you're using a bluish color. The eye sees this as darker somehow. Next, you'll probably want a really REALLY low light output. For me, even 50 is a bit bright, and seems a bit more like late afternoon than night. If you want a truly night-like map, I recommend setting the light_environment extremely low or deleting it altogether, and just working with regular texlights or spotlights strategically placed around your map. This will give the most realistic atmosphere, the only problem with it is that for outdoor maps with wide open areas, there's not always a good place to put lights. It works fine in city maps, though.