Currently, the Nexrad animation option runs through a few animation cycles and then stops. I find that behavior a little unintuitive, as most other consumer radar tools (like smartphone apps, web pages, etc.) work by toggling radar animation on and off.
Could you consider changing the menu option to read "Animate Nexrad (for 30 sec)" and/or toggling the menu option while it's animating to read "Stop Nexrad animation"?
The first time I used this in flight spooked me a little--I thought I might have gotten myself committed to animation for the remainder of the flight. Of course I realized shortly after that the animation stops by itself, but I'd bet that's an uncomfortable learning curve that almost everyone goes through unless they read and remember that tidbit from the user manual.