C3850 Touch Panel

Not sure if it's the right place since it's not about printing...
We use a c3850 for a not so intense use. 68000 copies in two years time and we had to change the transfer belt cause it broke (gear damage)and the clip that holds scanner belt broke as well. They are considered consumables so let's say all is fine.
My real issue is with the touch screen. There are parts of the screen that are intouchable. I have to keep pressing around them for like 2-3 mins to get a successful click. We have tried several times calibration but it never gets completed successfully, with and without the local authorized technician. The guideline states that the process will complete by itself in 30 secs, and after 15 mins, machine remains at the same status, and status led is still orange.
Konica minolta's support said that touch panel is sold complete with the screen and everything at a cost about 1/3 of machines cost. They gave me the option to buy a "memory board(WW)" at a lower cost, with no guarantee of success. That is a board that supposedly is in charge of the calibration.
Does anyone has any experience on that issue?