Inserting layers in Video Try Mode - Storyline 2

I am still learning to use Storyline, and I recorded the screen to show a new login procedure in our existing software, and then inserted a Try It series of steps using the same video.  One of the big issues with users is that they type their password and press the Enter key, which is what we DO NOT want them to do.  So I would like to insert an extra layer in which they complete their password, and if they press the Enter key, it will go to the layer that displays a large "BOOM!" graphic.  But the Base layer for this slide, which is in the Freeform question mode, used to have a Submit button which I changed to a "4" -- the last number in the password -- in order to validate they have finished typing the password.  If they complete the password, the video immediately moves on to the next "Try It" slide.  I do want them to know if they have mistyped the password, but don't want it immediately to move on to the next slide.  I want to know what they do next -- and if they press Enter, I want it to move to the "BOOM" layer. 

Next, I tried inserting a completely new slide that comes up after they type the "4," and asks what they should do next.  I added the "BOOM" layer to that slide, with "Enter" as the trigger.  If, on the other hand, they perform the correct step of clicking the "Log On" button, it moves them to the next "Try It" slide.  In this latter scenario, if I preview the single slide, it works.  But if I preview the whole scene, it does not.

Is there a way to do this?  I would appreciate any instruction that tells me how to work with newly inserted slides or layers in the Try mode!