Hi chrislikesblue,
Glad to hear about your good news! I'm waiting for the ICAO test result and I expect it should be fine. So next stage will be medical check.
In the technical interview, you will be asked questions related to aviation. It begins from basic knowledge and continues to drill down until you can't answer. That's what I know from a friend. So at least you should have a solid understanding of the basic stuff.
Did you do the group exercise? Or it will be done on the same day as the technical interview? Do you know if the informal lunch is still there?
I learn that they are keep interviewing candidates passing the Ap Test for this DA16. So chances still there. Keep it up folks!