I tried and tried and TRIED to make the engine change the lighting from day to night to day again, I tried tons of ways. The basic issue I ran into is the script command to change an Atmosphere Trigger's atmospheric settings ended up just corrupting the trigger and crashing the game. Maybe I didn't do it right, but I couldn't get it to go after hours of tests.
Did you ever make progress on this? I had this same issue and seemingly fixed it by NOT making the atmosphere trigger global.
This is counter intuitive to everything normally done in the story editor but it seems to work.
I still can't find a solution for the issue of idle characters though. When you aren't moving for long enough the atmosphere wont change.
