I've managed to export Navbox routes to my Aera. It worked, but badly. The moment you start making even small route changes (through some airspace instead of around, or vice-versa, 10 mile dog-leg around a CB...) the Aera does not handle it at-all well, constantly trying to drag you back onto exactly the planned route.
I've stopped doing it that way. I do a standard PLOG, and simply use "direct to" waypoints in turn on the Aera. That works fine, without mucking about, and gives me all the updates and situational awareness I need.
G