Drag and drop feedback using changing states

One way to do this:

For each dropped item, duplicate the Normal state twice and call one Drop Correct, and the other Drop Incorrect (the built-in names.) set the interaction to show the result states immediately. It will change the states, but the learner won't see the difference. For each dropped item, create two different states, with made-up names, like MyDropCorrect, etc. The triggers on the validate-object would be "Change state of DropItem1 to MyDropCorrect if state of DropItem1 = Drop Correct", and "Change state of DropItem1 to MyDropInCorrect if state of DropItem1 = Drop Incorrect". You would need these two triggers for each drop item.