I get the following error message:

Error while running event crafting_combinator::on_gui_opened (ID 83)
crafting_combinator/control.lua:151: attempt to index field '?' (a nil value)
stack traceback:
crafting_combinator/control.lua:151: in function <crafting_combinator/control.lua:147>

This occurs after I create a copy using ctrl-c and then try to click on a copied combinator, either a crafting or recipe combinator.

Just tested and it happens after blueprinting too.

I am running other mods, will experiment with disabling them to see if I can pin down a conflict for you. At the moment I can say it's not Shortwave or Construction Drones.

Running no other mods, placed a combinator next to a tier 3 assembly machine, hit "r" to rotate and got this error message.

Error while running event crafting_combinator::on_tick (ID 0)
crafting_combinator/control.lua:115: attempt to index field 'assembler' (a nil value)
stack traceback:
crafting_combinator/control.lua:115: in function <crafting_combinator/control.lua:112>