Hi @andypiper,
Sorry to hear about the troubles.
Currently flashing the RTL firmware to Wio Terminal is only possible using Windows, Mac and Linux (X86). Unfortunately, you cannot use the RPI 400 to flash the firmware. Could you please use Windows, Mac or Linux (X86) to flash the firmware? The libraries I have shared above are all up-to-date.
Also, if you are looking into more MQTT examples, please follow the examples available on our wiki pages:
And also, for even more MQTT examples, which connect Wio Terminal to ThingSpeak, Adafruit IO, Microsoft Azure IoT, Google Cloud IoT and Node-RED, please follow this YouTube playlist.
Hope it helps!
Best Regards,
Lakshantha