I installed PBRT on my Intel-based MacBook. In addition to PBRT I also installed OpenEXR and libTiff. The building went smoothly. I did not encounter any issues once the libraries were installed.
In order to speed up the rendering process I reduced my test image resolution to 200x200 pixels. I also wrote a short bash script to run program and to subsequently open the images after it had finished executing. I also kept my pixel samples to 1 and 2 while testing to speed up the processing. Once I was happy with my results, I increased the samples as well as the resolution.
To place the lights, I examined the examples as well as the diagram describing the scene setup. I tried to match the shapes and darkness of the shadows as best I could by tweaking the position, intensity and angle of the lights. When lighting the first 2 scenes this was fairly straight forward. It became more complex as more lights were added to the scene. For the 4th configuration, I worked on each light individually with all of the other lights turned off. I used basic trigonometry to calculate the angles that the area lights should be rotated by once translated.
I experimented a little bit with the properties of the lights (color, position, size) to see what effect the changes would have on the scene.