The solution for the one light problem is definatly mental ray. although, you dont need to use just one light because the window is your main light source. you can use multiple lights to cause a graidient shadow effect. Look into using fake GI (GI JOE). If you want to say in maya renderer instead of Mental Ray this may be the answer for you.
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And after calming me down with some orange slices and some fetal spooning,
E.T. revealed to me his singular purpose.
--TOOL, 10,000 Days---
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