Ctrl + Mouse Click to Advance - Possible?

In the course I'm working on, I want the user to select several options from a list and it uses typical Windows behavior - the user would click and hold ctrl and left mouse click each option.  When I recorded the screen in Captivate 7, the dialogue box states this instruction but when I test it, i can advance by only using the mouse.  Is there a way to force the user to use both the ctrl key and mouse to advance or else get a failure caption?

Thanks!