Drag and Drop and Revealing Info as you go

Hi

I have another question, I hope you dont mind.....I am quite new to Storyline but learning fast.

I'm trying to put  my first drag and drop question together and I can manage a very basic interaction whereby it drags and drops and pings the object back to start if object dropped in the wrong place.  But, what I want to do is a bit more.  Essentially I would like a little pop up to appear when the learner drags to the right place to reveal some extra text to give them a bit more info about the answer they gave.

I've tried to add some layers to reveal a character with "a well done that's right and here's a bit more info" but for some reason it does not like my layering.  With the layers it won't do the reveal and then continue with the drag and drop. 

I have about 10 statements that I want the learner to drag either to a "benefit hotspot area" or to a "risk hotspot area".  If the learner is right I then want a little message that says " that's right, doing this helps in this way" or words to that effect.  And then I want to allow the learner to continue with the rest of the excercise until all the drops have been put in the right hotpsot area and the helpful extra info has been relayed.

 My question is do you have to do the whole drag and drop excerise in one go before you can show more info about a particular choice that was made?  Any top tips for layering and triggers for this purpose if what I want to do is possible?

So many thanks to any helpful advice.  Going a bit loopy loop here!