ZWO camera focuser

Will be a focuser for ZWO sky-cams - one day.
Initial, experimental project!
Two STL part-files are printed.
One fits (badly) on the ZWO camera lens itself. Friction-fit only.
The other holds the ZWO camera body and the stepper motor.
The stepper motor is this one : https://ebay.to/2WYtGDV
Take care: the motor gets HOT, so settings for the driver needs to be worked out.
Currently I am using this driver: https://ebay.to/2L8siYc
and a piece of Arduino software that is easily found online.
Improvements are very welcome, and needed! Remember: the motor gets HOT!!!
To use in reality, you probably want to set up the driver from Python on a Raspberry Pi.