Script stops on touchpad click

[tomhk]

Hi, I am trying to disable ctrl+shift hotkey. It stops running for some reason.

This is my simple script:

^+::Return

I run it and it looks OK, but on the first touch on my touchpad it would stop working.
Actually it stops running also if I use alt+TAB to switch window etc...
I have Win 8.1

How to fix this?
thanks