The problem is the negligence in failing to resolve the issue. We have Visual Vibrant and impressive lighting packs like Action & Stuff, yet they can't fix this? Considering this Halloween texture pack dates back to the Xbox 360 era—and the lighting has reverted to vanilla—the magic has basically been ruined.
The only step needed to reproduce the issue is to purchase this texture pack and load any map seed.
The expected result is an orange sky with purple clouds and faint green lighting.
The actual result involves multiple bugs: the sky is the default "vanilla" blue, and the lighting on everything else is also vanilla. This is just the tip of the iceberg regarding how poorly maintained this texture pack is; the question is, when will all this be fixed?