If the 12 Step is not connecting to the editor but is showing up in other applications, there are a few things to try out.

1. Try unplugging the 12 Step and plugging it back in.
2. If you plugged the 12 Step in after opening the editor, try it the other way around. Connect the 12 Step, then open the editor. If you're already doing that, try it the other way. The order of operations can 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 single class-compliant MIDI device to be connected to a single application at a time. If, for example, the editor and Ableton Live were open at the same time then the 12 Step would only be able to work with one of them.
5. As a last resort, try manually reinstalling the firmware on your 12 Step. This is essentially a factory "reset".
6. If you are running Mac OSX in a language other than English there are a few steps to go through to connect to the Editor. You will only  have to do this once: 
• Navigate to the MIDI window of your Audio MIDI Setup, which can be found in System Preferences.
• Delete the 12 Step icon from the MIDI settings while in your preferred language with your device unplugged.
• In System Preferences where you select your language, select English and delete your preferred language.
• Boot into English and connect your device. Make sure the 12 Step device icon appears in the MIDI settings window.
• Now you should be able to open the editor and verify the connection.
• Boot back into your preferred language, and you should be good to go.
7. If none of the above options resolve the issue, contact KMI tech support.