You want the shadow and city lights to move over time? Only thing I
can think of is rendering 6-12 versions of the city lights tileset with
transparency for the day/night boundary, and layering those over your
base (day side) tileset. You probably don't even want the shadow
effect turned on, as it will make the city lights completely dark.
You might get away with as few as 6 renderings if you have a soft
shadow edge and can layer then like:
time+4 hours: 20% opacity
time+0 hours: 100% opacity
time-4 hours: 20% opacity
base layer: 100% opacity
by progressively increasing (and decreasing, for the trailing edge) the
opacity of the past and future city lights layers, you could avoid to
much jerkiness in the movement of the night/day boundary.
But... that requires at least 6 sets of the city light tileset with
alpha transparency burned in and viewing four tilesets at once,
resource hungry. At least you could link the files that were identical
across periods to save disk space.