[Help] Script not working on Windows 7 64bit ?

Im just a begginer in scripting i just follow the tutorial on youtube about AutoIt
can Anyone help me about my Problem...
I have a Code copied in AutoIt Tutorial on youtube with this code

HotKeySet("[UP]", "up")
HotKeySet("[RIGHT]", "right")
HotKeySet("[DOWN]", "down")
HotKeySet("[LEFT]", "left")

While 1 = 1
Sleep(1000)
WEnd

Func down()
$pos = MouseGetPos()
MouseMove($pos[0], $pos[1] + 1, 1)
EndFunc   ;==>down
Func right()
$pos = MouseGetPos()
MouseMove($pos[0] + 1, $pos[1], 1)
EndFunc   ;==>right
Func left()
$pos = MouseGetPos()
MouseMove($pos[0] - 1, $pos[1], 1)
EndFunc   ;==>left
Func up()
$pos = MouseGetPos()
MouseMove($pos[0], $pos[1] - 1, 1)
EndFunc   ;==>up

in the tutorial I see that the OS used is Windows 7 and the Script is Working

My question is how come the Script is now working on my Desktop Computer just wondering.. I hope Someone with a good heart help me, because I already spend this whole day searching in google for answers but I didnt find anything so I came here in the forum thanks.

Oh I almost forgot this is the link of the Video Tutorial I follow that is not working on my Desktop