Ctrl+X on an I/O pole results in the following error

Error while running event compaktcircuit::on_player_setup_blueprint (ID 70)
__compaktcircuit__/scripts/processor.lua:237: attempt to index local 'entity' (a nil value)
stack traceback:
    __compaktcircuit__/scripts/processor.lua:237: in function 'register_mapping'
    __compaktcircuit__/scripts/processor.lua:266: in function <__compaktcircuit__/scripts/processor.lua:261>

Thanks for reporting
I cannot reproduce it but it should be fixed in release 0.0.10

It is :)