• Hide (close) myCNC software to get Mate Desktop
• open console program (MATE Terminal)
• type calibration software name in terminal - “xinput_calibrator” and press enter
• Calibration software window will appear
• Follow the instructions and click 4 points the software will offer you
• Open File Manager (“operator's Home icon on Desktop),
• Go to File System / etc / X11 / xorg.conf.d
• On the file 99-calibration.conf click Mouse Right Button and select Open as Administrator
• Copy (replace if already present in) the data from xinput_calibrator to configuration file “99-calibration.conf”
• Press “Save” button, close Editor window.
• Restart the computer
• Notice: you might need to repeat this procedure in case “Swap” option was changed while calibration.

Short video about Touchscreen calibration (on Russian only)

Видео калибровки сенсорного экрана (по-русски)