im in contact with DUO myself. they will provide some api changes to finish the correct loading of calibration info from device. currently i have a workaround but cant release the code since its very dirty as soon as i've cleaned it up, i will make a pull request. regarding the logs it is due to the current version, obviously it tries to load the on-device calibration but there is none because there is no checking before if there actually is a calibration on device. but if the user wants to use the old calibration files, just set the "use_DUO_calibration" to false. that should do it currently.