If the K-Board is not connecting to the editor there are a few things to try out...

1. Try unplugging the K-Board and plugging it back in.
2. If you plugged the K-Board in after opening the editor, try it the other way around. Connect the K-Board, then open the editor. If you're already doing that, try it the other way. The order of operations can sometimes affect the results.
3. Try restarting the computer. It's amazing how many infuriating tech headaches can magically disappear with a computer restart.
4. If you're on Windows, make sure all other audio/MIDI applications are closed before opening the editor. Windows only allows a class-compliant MIDI device to be connected to a single application at a time.
5. As a last resort, try manually reinstalling the firmware on your K-Board. This is essentially a factory "reset".
6. If none of the above options solves the problem, contact KMI tech support.