This issue is now resolved. Thanks! https://github.com/pycom/pycom-micropython-sigfox/issues/77#issuecomment-334796725

Thanks for the super fast reply @robert-hh I am using bare board yes i can successfully connect to the device- in normal boot i get the python prompt, and with the jumper on GP23 i get "waiting for download" Pc is connected to the internet As above GPIO0 is tied to ground I have just solved the issue- i had selected the south african server in the menu, which failed. I now selected Europe (because it's also RCZ1) and this worked perfectly. Thanks again for the help!