I've integrated lights into the tile map, and I've allowed the editor/game to place, save, and load lights.
The yellow dots and the red polygons are there only for debugging purposes only, and I will soon get rid of those as I smooth out the system.
I also ditched the scenegraph system, as it was too complicated for what I wanted to do, and instead resurrected my old Camera class which allows simple transformation of the screen to give a scrolling effect. The new camera extension can be found in my ArcLib svn.
Lights are a really nice way of bringing the detail out in the scene, and prevents it from looking boring and repetitive. Thanks Christian K and OrangyTang!
So, for the lights, it seems like I will be using those for a 'Fog of War' type system for the bots. The bots will have a limited vision range, which the programmer can see by the current area it illuminates.
Now that lights are in, the next big step will be to integrate the lights and tilemap with the excellent Blaze physics system.