My game crashed on this new version:

785.726 Error MainLoop.cpp:1382: Exception at tick 224116378: The mod LTN Combinator Modernized (2.1.0) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event LTN_Combinator_Modernized::on_pre_build (ID 9)
LuaItemPrototype doesn't contain key valid_for_read.
stack traceback:
[C]: in function 'index'
__LTN_Combinator_Modernized/script/ltn_combinator.lua:1970: in function 'handler'
core/lualib/event_handler.lua:47: in function <core/lualib/event_handler.lua:45>

Thanks.

How to reproduce:

1) Open the GUI of some existing LTN Combinator
2) Close that GUI
3) Put a new LTN combinator (The game also crashed with any other combinator) from the inventory on hand and build it!
4) Crash!!!

Thanks

Just posted a fix for this one. Thanks for the report!