Hmmm.. I thought it should be that simple too. But for some reason that didn't work for me. Here's what I did, maybe I am missing an important step.
1) I created a sprite object and set the "initial visibility" to invisible
2) I added a mouse object
3) I went to the event list and set Mouse --> On Left Button Clicked --> Sprite Set Visible
when I go to run the game, I click all over the screen and nothing happens
am I missing something?