I hope you have found out why your Edge creaks and you will share with me. We bought a 2013 Edge and love how it handles and the features. However we are very disappointed with the vista panoramic roof. It squeaks at any speeds and the on rough roads it has a rattle. The squeak nearly drives me crazy, and the rattle sounds like the car is falling apart. We paid a lot of money for this car and feel it sounds like an old rattle trap at times. We took it to our dealership and of course the same old, same old...we cannot duplicate what you are saying is happening. And of course they have not had any anyone else with this complaint. They used silicone spray on the underside of the glass roof but it is very temporary squeak relief..maybe a day or so (squeak sounds like glass rubbing against rubber). We know the squeak is coming from the roof because if we open the roof the squeaking stops. I wish we had never decided to get this roof, even though I really like the roof. Think Ford should try to resolve this problem as I have read on Edge forums that Ford has Service bulletin TSB 07-16-11 regarding this problem. So they are aware of the problem. We are so frustrated and embarrassed when we have people in our vehicle and they ask what the noise is!
