I almost forgot, if you read the following FAQ it will give you the general concepts and terminology for what you were going to do. Basically you are going to use a custom DTH, that’s what the tweaker is. Once you have made the assignment through the web interface, you will be able to go into the smartthings app, go to the device, open its details, and make your changes.
The difference is you are going to go back to using your original DTH once you have the settings saved.