Oh, BTW, here's one of my renders with the ambient light from outside the windows...
hence why the render looks quite flat... 
Ambient lights are baaaaad! seriously! They are IMHO about as useful as an ashtray on a motorbike! Just thinking actually look at my old WIP that might give you some ideas on how to light a room in a warm and fuzzy way (i didnt get it 100% right but :p)
https://forums.simplymaya.com/showthr...ighlight=plane
Alan
Technical Director - Framestore
Currently working on: Your Highness
IMDB