The game crash when I tried to construct a steel chest:

291.172 Error MainLoop.cpp:1284: Exception at tick 90483328: The mod fafu inserter (1.1.6) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event fafu-inserter::on_pre_build (ID 9)
fafu-inserter/control.lua:119: attempt to index field '?' (a nil value)
stack traceback:
fafu-inserter/control.lua:119: in function <fafu-inserter/control.lua:103>

Thanks

I have try to reproduce the bug, but it don't happened.
Can you give me more information?
What have you done before the game crash?

The game still crashs after this recent update (I have removed the mod before and was trying again now)!
I don't have done anything special. Just research all the new techs provided by this mod, build 5 of each inserter and deploy some steel chests (to test this mod).
The same error happened:

454.469 Error MainLoop.cpp:1284: Exception at tick 157644210: The mod fafu inserter (1.1.7) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event fafu-inserter::on_pre_build (ID 9)
fafu-inserter/control.lua:119: attempt to index field '?' (a nil value)
stack traceback:
fafu-inserter/control.lua:119: in function <fafu-inserter/control.lua:103>
481.552 Quitting: user-quit.

Thanks

Ok, I found a problem, if the mod is activated mid-game. (with the same error message)
I hope i solve all issues.
Can you try the new version and check if this works for you too?