had nearly the same problem.
asking the support for a method via console i got this idea:
Access console and delete " /data/system/calibration " file .
Reboot device and it will ask for calibration.
additional from me....
to access the console take the serial cable and connect it to uart1. start a terminal on your (serial) connected computer (eg putty, token2, ...) with 115200, 8, n, 1 setting and access the console.
rm /data/system/calibration [return]
reboot and you get the touch calibration screen