monitor script ?

[mastermark]

Hi guy just wondering if anyone could help
Im after a script that will monitor a .exe and when the exe gives out a command trigger i need it to turn on a led
{
IfWinExist, Breeze Systems Photobooth
{
WinGetTitle, Title, Breeze Systems Photobooth
if Title contains 1.jpg
{
if PreviousTitle not contains 1.jpg
{
LEDOn() ; The first picture screen has just been displayed - turn relay #2 on
}
}
else if PreviousTitle contains 1.jpg
{

I have this code but i need it to work on a command trigger another software give out . This code just looks for a title

So i want to monitor a .exe then when the trigger capture_start gets triggered i want it to say LedOn() . Then when the .exe triggers capture_start i want LEDOFF()

Im not sure how to do it been at it for hours now can someone please help