Error while running event integratedCircuitry::on_robot_built_entity (ID 14)
...cuitry__/control/compact-combinator-allowedBuildings.lua:31: attempt to index local 'player' (a nil value)
stack traceback:
...cuitry__/control/compact-combinator-allowedBuildings.lua:31: in function 'compactCombinator_checkSurfaceBuildings'
integratedCircuitry/control.lua:72: in function <integratedCircuitry/control.lua:69>

I pasted the following blueprint inside the IC. Didn't realize it still had train stations inside it. https://pastebin.com/mVx5d5dk

And another one for you.

Error while running event integratedCircuitry::on_gui_opened (ID 83)
Gui element with name integratedCircuitry.compact-combinator.back already present in the parent element.
stack traceback:
integratedCircuitry/control/compact-combinator.lua:69: in function 'open'
integratedCircuitry/libs/control/gui.lua:124: in function <integratedCircuitry/libs/control/gui.lua:114>
stack traceback:
[C]: in function 'add'
integratedCircuitry/control/compact-combinator.lua:69: in function 'open'
integratedCircuitry/libs/control/gui.lua:124: in function <integratedCircuitry/libs/control/gui.lua:114>

This one was rather random as I entered into the IC.

Another one...

Error while running event integratedCircuitry::on_built_entity (ID 6)
...tegratedCircuitry__/control/compact-combinator-ghost.lua:56: attempt to index local 'entity' (a nil value)
stack traceback:
...tegratedCircuitry__/control/compact-combinator-ghost.lua:56: in function 'indestructible'
...tegratedCircuitry__/control/compact-combinator-ghost.lua:13: in function 'build'
integratedCircuitry/libs/control/entities.lua:277: in function 'entities_build'
integratedCircuitry/control.lua:64: in function <integratedCircuitry/control.lua:62>

This one was when using a blueprint to copy-paste an IC.