SceneColor + Switch (Default false) + Instance set to true = causes LightAttenuation stack error + wrong results

What: SceneColor + Switch (Default false) + Instance set to true = causes LightAttenuation stack error + wrong results.

Platform: Windows OS 7

Branch: Unreal Launcher

Build version: 4.18.0 + 4.18.1 + 4.18.2

Project Package: Editor

Problem: LightAttenuation stack error

How to solve this:

Do not use: Switch (default set to false)

Instead use: Switch (default set to true) and set via Material Instance the parameterbool to false

MyMaterialProject.zip

LightAttenuationCallstackError.txt

== Screenshots ==

https://www.dropbox.com/sh/yki2dhjbh6tj43n/AAC4bUdizXBgWzrdPuPTSPq2a?dl=0&preview=Screenshot_1264.png

Good:
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Wrong:
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