I found a very specific crash state, probably due to LTN Screensaver hiding the cursor.
1) run LTN Screensaver
2) wait until it ports you into a train
3) click the landfill button
Result:
Error MainLoop.cpp:1202: Exception at tick 120083391: The mod Landfill Everything (0.18.1) caused a non-recoverable error.
Please report this error to the mod author.
Error while running event LandfillEverything::on_gui_click (ID 1)
__LandfillEverything__/control.lua:203: attempt to index field 'cursor_stack' (a nil value)
stack traceback:
__LandfillEverything__/control.lua:203: in function <__LandfillEverything__/control.lua:199>