For day and night system, I have an idea. We could create some more or less opaque black prop (ex. dawn/dusk 25% opaque and night 50% opaque) and add them to all the tiles on the map (or one huge prop at position <0,0> with a pre-defined size which must match the Area size)!
To do it dynamically, we would need a script for that, and better, the "OnEnter" script property called (it is not implemented at the moment). Don't know if it will give a problem with the engine, such as processor/graphics lag or crash...
I also suggest that the windows of spell selection and traits could contain groups, perhaps, so they are sorted by categories? And also inventory?