The moment when any (constant,decide,etc) combinator which has been set up to output launch condition is wired with silo, the below error happens.
Error while running event CircuitLaunchableRockets::on_tick (ID 0)
CircuitLaunchableRockets/control.lua:124: attempt to index field 'space_location' (a nil value)
stack traceback:
CircuitLaunchableRockets/control.lua:124: in function <CircuitLaunchableRockets/control.lua:27>