Die Mod Belt Visualizer (2.0.2) hat einen Fehler verursacht, der nicht behoben werden kann.
Bitte informiere den Autor der Mod über diesen Fehler.

Error while running event belt-visualizer::on_tick (ID 0)
belt-visualizer/scripts/highlight.lua:142: attempt to index field '?' (a nil value)
stack traceback:
belt-visualizer/scripts/highlight.lua:142: in function 'add_to_queue'
belt-visualizer/scripts/highlight.lua:185: in function '?'
belt-visualizer/control.lua:338: in function <belt-visualizer/control.lua:306>

a very similar error, when i'd just closed an unrelated gui window. space age 2.0.77, many other mods including Whistle Stop Revived, Renai Transport and AAI Loaders. i'll try to post a screenshot somewhere, it's full of clues.

The mod Belt Visualizer (2.0.2) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event belt-visualizer::on_tick (ID 0)
belt-visualizer/scripts/highlight.lua:142: attempt to index field '?' (a nil value)
stack traceback:
belt-visualizer/scripts/highlight.lua:142: in function 'add_to_queue'
belt-visualizer/scripts/highlight.lua:340: in function '?'
belt-visualizer/control.lua:338: in function <belt-visualizer/control.lua:306>

screen shot: https://imgur.com/a/RoxVbU2

totally crashed the game. been playing for many hours before this happened tho. belt vis was working great.

those belt upgrades you see marked on the screen - Kruise Kontrol was busy upgrading those when it crashed.