NullReferenceException: Object reference not set to an instance of an object
  at AmericanRailroadSignals.LoadingExtension.OnLevelLoaded (LoadMode mode) [0x00000] in <filename unknown>:0
  at LoadingWrapper.OnLevelLoaded (UpdateMode mode) [0x00000] in <filename unknown>:0
Rethrow as ModException: The Mod C:\Users\Julian\AppData\Local\Colossal Order\Cities_Skylines\Addons\Mods\AmericanRailroadSignal [AmericanRailroadSignal0.dll] has caused an error

UnityEngine.DebugLogHandler:Internal_LogException(Exception, Object)
UnityEngine.DebugLogHandler:LogException(Exception, Object)
UnityEngine.Logger:LogException(Exception, Object)
UnityEngine.Debug:LogException(Exception)
LoadingWrapper:OnLevelLoaded(UpdateMode)
<LoadLevelComplete>c__Iterator9:MoveNext()
LoadingManager:Update()

(Filename:  Line: -1)