I got a crash almost immediately after loading the game with the mod

48.808 Error MainLoop.cpp:1435: Exception at tick 110894421: The mod Spoilage Scanner (0.2.0) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event spoilage-scanner::on_tick (ID 0)
LuaEntity API call when LuaEntity was invalid.
stack traceback:
[C]: in function 'index'
__spoilage-scanner/control.lua:54: in function 'update_signals'
spoilage-scanner/control.lua:136: in function <spoilage-scanner/control.lua:133>

Hi, I fixed the crashes and made a pull request

https://github.com/rekales/spoilage-scanner/pull/2

Merged and released, much thanks.