I've just had a quick wander around the map, and I've got to say that what everyone is saying about the shadows, or more accurately the contrast, is true - it's way to intense.
I understand what you're trying to do with the nature of how shadows are cast at sunset/rise, to give it that dramatic look, but what you forget is that the Battlefield engine is not able to display such high contrasts realistically, as your vision does not adjust itself to the light and shadows as it would in real life (as Valve developed for Half-Life2 Episodes 2 & 3). Which is why you need a certain amount of ambient light to see what you're doing, not much, but just enough to make out contours and shapes.
I'm afraid I can't really comment on the gameplay of the map, as I'd need a few other players in there with me, but I really like the idea :-)