One thing that it could have been, is a limitation in the current platform where the Cayenne web dashboard needs to be open at the time of initial widget creation for any LoRa sensor data received. So, for example, you could send us temperature payloads for days, but the dashboard needs to be open while at least one payload is received which then creates the initial widget. Once that is in place, Cayenne will happily log all further temperature data on the same channel without any need for the browser to be open.
Was there another issue you needed me to investigate with the DevEUI? If so please let me know, I'm glad to hear that the initial one has resolved itself.