Mon Jun 25, 2012 5:12 pm by massimo
Well quickly looked at your scene. Some basic considerations:
1) You have some commercial textures in the scene so I suggest you to change them if you want to share the scene;
2) Your lighting is made by the sun+a spot light+a global and also you have an image on a plane (the plane will stop some sun's light) as background. Definitely a bit messy. Also the spot light has attenuation set to "none": better always use "inverse square". As a start, and as a general rule of thumb, I would go with the sun only or the hdri only;
3) Volume lighting is disabled;
4) I would tick "soft shadow" under the sun's settings;
4) The curtains have thickness. No need for that i believe.