Dusk lighting in FSX

The new demo is great but there's one thing that niggles me. If I set the time to dusk the ground lighting does not come on. Although the world is pretty dark it's as if there's been a huge power cut. Lights only come on maybe an hour later.I remember a similar situation maybe in FS2002. I found I could get the lighting on at dusk by changing a cfg setting, I think it was DAWN_DUSK_SMOOTHING. Changing this has no effect in the demo.Does anyone know how to get the lights on at dusk?Best regards, Chris