Here is the way I have mine setup. All that is needed for basic control in the Berto_MQTTBridge configuration is the server info. Everything else for Sonoff relays is done through the Berto_SonoffRelay and Berto_RelayLight. First make sure what topic you have configured as the Topic on the sonoff under Configuration> Configure MQTT and make sure that that is entered exactly (case sensitive) under the topic on the Berto_SonoffRelay configuration in composer. Once that is verified then a standard connection needs to be made between Berto_SonoffRelay and the Berto_RelayLight. Let me know if this helps or you have any more questions on it.