What I've figured out how to "fake" using CS2D is a similar effect where an HDR-like effect is overlayed on the map, to brighten and darken certain areas like cloud shadows. But the key to this is that it moves and changes. So as you're playing, it will seem like there really is a sun and a bunch of clouds above you, and as time passes, the lighting dynamically changes.
Granted, it's not nearly as spectacular or high-def as most games, but it does create an interesting atmosphere, though still a bit corny.
I'm not going to say anymore on my pseudo-HDR lighting. You'll just have to wait 'til the map is finished to find out what I mean.