When player joins the game, this exception occurs:

The mod Picklock's Inserter (1.110.6) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event Picks-Inserter::on_tick (ID 0)
__Picks-Inserter__/control.lua:112: attempt to index local 'myPlayer' (a nil value)
stack traceback:
    __Picks-Inserter__/control.lua:112: in function 'PI_set_controls'
    __Picks-Inserter__/control.lua:584: in function <__Picks-Inserter__/control.lua:579>

It was tested with headless server 1.1.87 stable on Debian 11
Error occurs on trying to connect to this server, server drops after this error aswell:

94.121 Error MainLoop.cpp:1382: Exception at tick 0: The mod Picklock's Inserter (1.110.6) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event Picks-Inserter::on_tick (ID 0)
Picks-Inserter/control.lua:112: attempt to index local 'myPlayer' (a nil value)
stack traceback:
Picks-Inserter/control.lua:112: in function 'PI_set_controls'
Picks-Inserter/control.lua:584: in function <Picks-Inserter/control.lua:579>

94.121 Error ServerMultiplayerManager.cpp:92: MultiplayerManager failed: "The mod Picklock's Inserter (1.110.6) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event Picks-Inserter::on_tick (ID 0)
Picks-Inserter/control.lua:112: attempt to index local 'myPlayer' (a nil value)
stack traceback:
Picks-Inserter/control.lua:112: in function 'PI_set_controls'
Picks-Inserter/control.lua:584: in function <Picks-Inserter/control.lua:579>"

94.121 Info ServerMultiplayerManager.cpp:813: updateTick(0) changing state from(InGame) to(Failed)

Hi,

First of all, I would like to apologize for not responding to your posts sooner. Unfortunately, I overlooked them.

I have looked at your problem and fixed the error. At least the error no longer occurs for me on a headless server.