Beams do not illuminate from light instances when future lighting technology is enabled. It works with every other lighting mode.
It should be noted that light influence works on particles in future.
Here is the exact setup used in the screenshot.
Beam.rbxm (6.6 KB)
Beams should be effected by Light Influence when Future lighting technology is enabled.
When looking at different lighting modes such as voxel;
You can see that light influence works and the beam becomes illuminated with the red light.