First off, thank you so much for doing exception catching and gracefully handling the problems.

So yeah, last few days when I've tried to move big power poles I've been having this exception pop up and while the pole moves the lights stay where they are at.
https://gist.github.com/jarquafelmu/a49bee72c6e8e12a1043b184c767b16b

save game:
https://drive.google.com/file/d/18MhODCN109bX9bamxObepHAvpI9n0IqP/view?usp=sharing

it's weird, i can't seem to reproduce the issue, when i move the power poles there are no problems
can you send a screenshot of the exception occurring?

for sure once I get it happening again, it seemed like it was only happening under specific circumstances that I had not been paying close enough attention to, because it definitely didn't happen all of the time

just had it happen again, It happened again when moving a big electric pole. though I have also been noticing some other strange behavior., some mod introduced buildings, like bob's metal mixing furnace, were picked up at the start of this play session, they left behind their lights and now no mod introduced building will spawn lights when placed down.

log
https://gist.github.com/jarquafelmu/d915b88009063d570c55b11bcfd9169f

save file:
https://drive.google.com/file/d/1U_J9xxoWftjqLDZfkioqKA6ZP8bZ9WBV/view?usp=sharing

to recreate:
use shift+left arrow or shift+right arrow on any big electric pole that has lights. already

examples
https://imgur.com/a/ElpLAlI

When it comes to the floating lights, try to check out the per save global mod setting

There is one that scans all lights periodically and removes any that don't have an entity anymore

when it comes to things not getting lights when placed down, i'm guessing it's only happening on mod buildings
i will try to investigate this

when it comes to the metal mixers, it seems like they were previously in the CommonEntities list but were removed

did this save previously have Hazard Lights Auto Lights?

because it seems all the metal mixer lights are invalid, meaning no entities are assigned to them

the problem should be fixed now
please do respond if the problem reappears