After first setting up the Echo Widget on the controller PC the user will be confronted with a form to enter the Activation Code that looks like this:
"The Widget Download page" is pretty vague. So, what you really need to do is to go https://mtsecho.com and login. Then, from the main menu on the left, click on 'Downloads' to get the the Downloads page. Once there, look for the MTS Echo download.
It looks like this:
Click on that image to go to the MTS Echo Download page. Once there, click on the blue 'Activation Code' button and your Activation Code will appear in a pop-up window like the one below.
Copy and paste that into the Widget form and you will be all set.