To begin the Calibration of the Touchscreen of the Explorer I & II using the Keyboard:
1) tap the Blue 2nd Function Key then tap the “W” to open the Start Menu
2) tap the “S” key on the keyboard
3) tap the “C” key on the keyboard
4) tap the “S” key / tap the “S” key again to highlight the “Stylus” icon
5) tap the “Enter” key
6) tap the Yellow “1st” key then tap the “B” key
7) tap the Yellow “1st” key then tap the “D” key
8) tap the “Alt” key then tap the “R”
9) Follow the on-screen prompts to Calibrate the touchscreen
10) When the little crosshair disappears tap the “Enter” key on the keyboard to save your Calibration settings
Now try using the Touchscreen again to see if this resolved the issue.