I still can't determine how to reproduce but the game crashes some times with this error:

The mod Rail Logistics Dispatcher 2 (2.0.24) caused a non-recoverable error.                                                                                               
Please report this error to the mod author.

Error while running event RailLogisticsDispatcher::on_nth_tick(2)                                                                                                 
LuaEntity API call when LuaEntity was invalid.                                                                                                                    
stack traceback:                                                                                                                                                  
        [C]: in function '__index'                                               
        __RailLogisticsDispatcher__/script/utils.lua:520: in function 'setTrainScheduleWithPreserveInterrupts'
        __RailLogisticsDispatcher__/script/train.lua:198: in function 'trainUpdateSchedule'                                                                       
        __RailLogisticsDispatcher__/script/entity.lua:1440: in function 'dispMakeDelivery'
        __RailLogisticsDispatcher__/script/entity.lua:1296: in function 'dispUpdate'
        __RailLogisticsDispatcher__/script/entity.lua:1511: in function <__RailLogisticsDispatcher__/script/entity.lua:1492>

Hi. Thanks for the bug report. I'll get to that crashing code soon. Now you can disable saving interrupts in the schedule in the mod settings (hack). This is what causes the crash.