Hi @ProfDrJones
When you calibrate a touchscreen on FLX, the calibration is saved along with a reference to your touchscreen's unique ID. It therefore sounds like FLX is unable to detect the touchscreen's ID upon reboot, and therefore doesn't apply the existing calibration.
Out of interest, if you just turn off the FLX overnight, but leave the external touchscreen powered (standby), do you encounter the same issue?
After calibrating the external touchscreen, please tap Z -> System Information -> System Info, and take a picture of this screen. If the external touchscreen's calibration is then lost upon reboot, please go back into System Info, and take a picture of this screen again. Please then email these two pictures to support@zero88.com, preferably with a link to your external touchscreen's manufacturer webpage. We will then be able to investigate further.
Please let us know if you have any questions.