we found one bug in touchscreen driver during out testing.
When I use only one or more fingers it works fine.
If I put metal sheet to display for few seconds (approx. 5sec) touch screen stops working.
After restart it works again.
I tried to debug WinCE driver and there are many messages from Atmel display controller.
I thing there is problem with autocalibration. Is it possible to upgrade firmware to display controler?
My hardware: Colibri T20, Windows CE7, Iris 2.0 board, Capacitive Touch Display 7" Parallel V1.0B