How to present to professional engineers.

Background: I am a senior structural engineering student getting to the end of my Capstone project. The project is to do a complete design of a two story commercial retail building.

In 4 weeks my group and I will present in front of a local engineering firm (lots of PEs).We are used to presenting our work in front of professors who have a basic idea of our capabilities and have known expectations of us. Does anyone have advice on what sort of things we should be sure to talk about or mention for our presentation in front of the engineers? If we were to present in front of any of the professionals on this sub what would you want us to mention about our design?