Repro step: just placed a recipe combinator on empty ground, not near a machine. Haven't unzipped to investigate further yet

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The mod Crafting Combinator (0.15.0) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event crafting_combinator::on_tick (ID 0)
crafting_combinator/script/signals.lua:19: attempt to index field 'signals' (a nil value)
stack traceback:
crafting_combinator/script/signals.lua:19: in function 'get'
crafting_combinator/script/signals.lua:93: in function 'get_highest'
crafting_combinator/script/recipe-selector.lua:8: in function 'get_recipe'
crafting_combinator/script/rc.lua:161: in function 'find_ingredients_and_products'
crafting_combinator/script/rc.lua:125: in function 'update'
crafting_combinator/control.lua:103: in function 'run_update'
crafting_combinator/control.lua:114: in function <crafting_combinator/control.lua:105>
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modlist

pumps-everywhere 1.2.0
bobinserters 0.18.0
boblibrary 0.18.0
bobmodules 0.18.0
Bottleneck 0.11.3
crafting _combinator 0.15.0
deadlock-beltboxes-loaders 2.3.3
DeadlocksStackingForPyanadon 0.2.0
electric_water_boiler 0.0.10
even-distribution 0.3.15
factoryplanner 0.18.6
FARL 4.0.1
FNEI 0.3.0
LogisticTrainNetwork 1.12.6
LTN_Combinator 0.6.0
LTN_Tracker_2 0.10.9
MaxRateCalculator 3.2.32
OpteraLib 0.2.1
ore-erase 1.5.0
production-monitor 0.18.0
pyalienlife 1.3.1
pyalienlifegraphics/2/3 v.who_cares
pycoalprocessing 1.6.2 + graphics
pyfuesionenergy 1.6.0 + graphics
pyhightech 1.5.4 + graphics
pyindustry 1.4.4
pypetroleumhandling 1.6.8 + graphics
py-quick-start 0.17.6
pyrawores 1.9.9 + graphics
qol_research 2.4.0
rso-mod 6.0.5
rusty-locale 1.0.5
Squeak Through 1.8.0
stdlib 1.4.1
WideChests 3.0.2

Was that in a new game or an existing save? And if it was an existing save, can I have it?

an existing save, I'll get it wrapped up later tonight. I'm pretty sure it's had crafting combinator in there since the beginning, but only recently got to the point of being able to even consider crafting one

sent the save, log, and local mod adjustments along in a pm

So I just had a look at the save and it seems to be a case of the migration script not running. I have no idea how that happened tho... If you have any details about how the update went, that could help (which version you updated from, did you see a popup when loading after the update?). Also, if you happen to have a version of the save from before the update, that might help too.

Btw, running /c __crafting_combinator__ require('script.signals').init_global() in the console will fix this, tho I imagine in your case it's not much of a problem since you weren't using the mod anyway, so just saving without it and reloading with it again would work too.

I will give that a shot. The save is just starting to get to the point where it'll be handy.

Sadly I don't recall exactly when crafting combinator was dropped in, or when the update kicked in. I don't think I saw anything noteworthy after updates, but there was a period that went through a lot of general mod shuffling a while ago.