In the pre-Sonar days, it was possible to bind the "MIDI/Audio reset" task to a computer keystroke. Now a reset is only possible by clicking on the icon in the main control bar. I frequently use a Contour Shuttle Pro and it was very helpful to be able to bind the reset function to the Shuttle and avoid using a mouse or touchpad. That's no longer possible. It would be very useful to be able to bind the MIDI/Audio reset to a key.

Kronosman, not sure if this will help ... I was similarly frustrated, as I tend to get a stuck key now and again (always on an organ or string patch so it goes on FOREVER), and it was a pain to try to navigate with a mouse to hit the reset during a live performance.  A keyboard mapping would be a huge help, but until that exists here's my workaround:
 
I use the AZSlow's AZController (a control surface plugin that lets you do some wonderful low-level stuff with any control surface, or even without one).  High level, think of it as being able to define whatever logic you want to execute in response to a MIDI event.  It exposes SONAR's command interfaces, and specifically lets you issue either a "Realtime Panic", or "Stop/Run the Audio Engine".  Note that a Realtime Panic also stops the audio engine.  
 
I have it setup so an unused solo button on my nanoKontrol stops all audio, pauses a moment, then re-enables.  If you don't have a control surface to play with, you could easily map it to do the same for some other triggering event (for instance, lowest key on your keyboard, or perhaps a chord of the bottom three keys to keep it from getting hit accidentally).