This tutorial will teach you how to use ies light in your sense. You need to install vray for rhino first to complete this tutorial.
1. Open your interior scene and then set Vray for rhino as the current rendering engine.
Tips: The scale of the objects is important, 1:1 is better.
2. In the Rhino command prompt, type visIESlight to create a light.
3. In the Light Properties window, click on Browse button to add an existing ies file you want to use.
4. Modify other parameters to meet your needs. It seems that the intensity of the light cannot change in this version. Done.