Sorry on the delay, I shut down Poser and the room scene at at 204 MB, it takes awhile to load up.

My units in Poser's preferences are set to FEET.
With in your shader they are set to INCHES (I believe).

The main center point light as well as the two spots are set at 7.326 above ground, the floor is 0.02 above ground. It is set at 70 inches (5.83 ft) for Intensity Distance.

The spot lights are both 3.64 feet left and right of center, 10 feet forward and angled down 12 degrees.