Can't get trigger to work

Hi, I'm completely new to Storyline and have a week to become familiar with it in order to produce interactive courses for teachers. At the moment, I'm just experimenting with setting triggers. I have created a map background and want the teacher to click on a country to see if it is a multilingual country or bilingual.  So I have created a rectangle shape which I placed on top of South America (which will be made transparent). I want to set triggers on the shape so that when the teacher clicks there, he/she will see a text box pop up saying multilingual.  To do this, I set the first shape's trigger to show the first layer and set the 'multilingual' text box to be on the first layer. But when I go into preview, I can't see the multilingual text box appear. There is a link on the rectangle shape as the cursor turns to a 'hand', but nothing happens. Help!! I just cant get this to work! Thanks!