Apparent Depth Map Precision Issues

Hello,
I’ve been working on a shader that renders point lights via PostProcessStage, but I have encountered an issue where there appears to be lost precision either in the depth buffer or in a matrix multiplication.
When I attempt to convert UV+depth to world space position and then convert back into uv coordinates, I get what appear to be precision errors.

Here is a link to a sandcastle that demonstrates this issue.

Would anyone know a proper workaround? I have attempted messing with the near and far ranges when processing the depth, but anything that fixes the visual artifacts causes incorrect world positions to be generated.

Any help is appreciated.