Stack trace/error log included below

I was adding new buildings and modules to MI when this happened. One weird thing happened which was that I added a module to the blank at the bottom and then changed that to a building.

53737.666 Error MainLoop.cpp:1285: Exception at tick 24228184: The mod Module Inserter (5.2.4) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event ModuleInserter::on_gui_elem_changed (ID 68)
ModuleInserter/scripts/gui.lua:677: attempt to index local 'entity_proto' (a nil value)
stack traceback:
ModuleInserter/scripts/gui.lua:677: in function 'handler'
ModuleInserter/control.lua:697: in function <ModuleInserter/control.lua:689>
53737.667 Error ServerMultiplayerManager.cpp:91: MultiplayerManager failed: "The mod Module Inserter (5.2.4) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event ModuleInserter::on_gui_elem_changed (ID 68)
ModuleInserter/scripts/gui.lua:677: attempt to index local 'entity_proto' (a nil value)
stack traceback:
ModuleInserter/scripts/gui.lua:677: in function 'handler'
ModuleInserter/control.lua:697: in function <ModuleInserter/control.lua:689>"

In fact this is easily reproduceable by putting a space exploration module 6 in the empty row at the bottom in a multiplayer game.

Link to code line, responsible: https://github.com/Choumiko/ModuleInserter/blob/master/scripts/gui.lua#L677

perhaps a nil check and early return here: https://github.com/Choumiko/ModuleInserter/blob/master/scripts/gui.lua#L653

Should be fixed in the next version