I've uploaded to the latest firmware and it seems to be working fine. (But It would be nice to have a change log. )
For people having print quality issues, I highly recommend this website as it did wonders for the print quality on mine.
https://teachingtechyt.github.io/calibration.html
With regards to the printer scratching the surface when you cancel a print.
I'm quite new to Arduino and programming, but on the Marlin website I find. This gcode.
G28. Auto home.
I should think that is what is activated when you cancel the print? And if the X is added then it will work as the other printers and raise the head a bit before returning.
Hopefully this will be added in the next update.
[Y] [Z]
Parameters
[O]
Optional. If the position is known then exit without homing. (1.1.9)
[R]
Raise before homing distance (1.1.9)
Flag to go back to the X axis origin
[Y]
Flag to go back to the Y axis origin
[Z]
Flag to go back to the Z axis origin