Touchscreen and BS Shd of the Templers DC

[MrTomD]

I've got a touchscreen based pc (wetab) with win7 and I tried to play Broken Sword Shadow of the Templars DC. But the touchscreen is not working properly. I have to put my finger on the middle of the screen and move it like a pointing stick. What did I wrong?

sry for my poor english :)