Weird Occlusion Error

I will see if I can describe the error since all my files are on my work computer so I don't have so much as a screenshot.

I am working on a definition to compute an idealized shade for the different facades of a tower to block a portion of the rays at the time of the peak cooling load for each facade zone. I also set up the geometry to export to either DIVA or Ecotect for comparison of the radiation on the facade before and after the shades.

I also wanted to use the Occlusion function to create a cull pattern to eliminate the sunshades over windows that are in shade from the context at the time of the peak cooling load. I am using the solar vector component from DIVA to set the ray vector for the peak load, the context for the obstruction geometry, and the center points of the glass for the sample points.

Everything is working beautifully except for the occlusion. It appears to work by culling the lower sunshades, but on closer inspection, it is taking the vector at a significantly lower altitude than the sun is located at during the peak hour. I noticed this because the pattern on the facade is the shape of a neighboring tower that would only overshadow our building at a lower altitude. Renderings of the facade with the sun correctly located showed different shadow patterns that what the occlusion was calculating.

I am not sure how to fix this. Anyone encounter this error and know what to do about it?