Entering DOS fields

I have an interesting situation I'm hoping to get some feedback on from you Captivate experts.

We have a section of training where we need to show staff how to enter things into our DOS system. For security reasons I can't show the actual screen, but I've included an image of what we're trying to accomplish.

Basically staff have to enter information into three boxes. Both SS and date of birth have three separate boxes. The current version of the Captivate training uses multiple text captions and actions to accomplish what we need to. The biggest issue is currently learners have to press the tab key to go to the next box, but in the actual DOS program it automatically advances to the next box.

My questions are:

1. How would you go about building this sort of interaction?

2. Is there a way to have it advance to the next box automatically after user has typed in the previous box?

I've also considered that if it would be better to go with a simulation on this instead of using screen shots and actions.

Thanks!