13372.565 Error MainLoop.cpp:1284: Exception at tick 71384560: The mod ⚠️ SearchlightAssault ⚠️ (2.0.1) caused a non-recoverable error.    
Please report this error to the mod author.

Error while running event SearchlightAssault::sla_gui_open_shortcut (ID 253)    
__SearchlightAssault__/control-gui.lua:559: attempt to index local 'sl' (a nil value)    
stack traceback:    
        __SearchlightAssault__/control-gui.lua:559: in function 'OpenSearchlightGUI'    
        __SearchlightAssault__/control.lua:295: in function <__SearchlightAssault__/control.lua:289>    
13372.565 Error ServerMultiplayerManager.cpp:91: MultiplayerManager failed: "The mod ⚠️ SearchlightAssault ⚠️ (2.0.1) caused a non-recoverable error.    
Please report this error to the mod author.

Error while running event SearchlightAssault::sla_gui_open_shortcut (ID 253)    
__SearchlightAssault__/control-gui.lua:559: attempt to index local 'sl' (a nil value)    
stack traceback:    
        __SearchlightAssault__/control-gui.lua:559: in function 'OpenSearchlightGUI'    
        __SearchlightAssault__/control.lua:295: in function <__SearchlightAssault__/control.lua:289>"    
13372.565 Info ServerMultiplayerManager.cpp:797: updateTick(71384560) changing state from(InGame) to(Failed)    
13372.581 Quitting: multiplayer error.    
13373.962 Info ServerMultiplayerManager.cpp:140: Quitting multiplayer connection.    
13373.962 Info ServerMultiplayerManager.cpp:797: updateTick(4294967295) changing state from(Failed) to(Closed)    
13373.964 Info UDPSocket.cpp:218: Closing socket    
13373.964 Info UDPSocket.cpp:248: Socket closed    
13373.964 Info UDPSocket.cpp:218: Closing socket    
13374.273 Info UDPSocket.cpp:218: Closing socket    
13374.273 Info UDPSocket.cpp:248: Socket closed    
13374.274 Goodbye

Thanks for the formatting suggestion.

It looks like this happens if a player somehow clicks on a searchlight to open the gui, but doesn't have the searchlight selected.

I should be able to put out a fix today.

Formatting is just done through markdown syntax, I think
https://www.markdownguide.org/basic-syntax

log here,
with 4 empty spaces in front of each line
of log

I have released version 2.1.0 which attempts to fix the issue. At the very least, it should prevent the crash.

Sadly, I couldn't reproduce the problem, so if it doesn't work, please post with any new error messages.

The new version should start to appear in the mod portal shortly.
If you don't see it in-game you can download it manually here: https://mods.factorio.com/mod/SearchlightAssault/downloads

Thank you for your report!

Now it works alright, but I noticed it now breaks LTN Manager. I'll post a new thread about it.