Attached Link: http://www.a1gems.org/Carrara/proxtesthC4.wmv

The example seems to work in C5. Its subtle .. proximity is used to blend the gray color over distance to help match the background. Its more noticable with bright colors. here is a quick sample movie using proximity with distance fade and location. Moving object changes color and glow depending on location. and distance to other object , or nulls.