Setting up response groups will require you to add your PC's hostname to the groups interface. This will allow your Little Green Button to pick up the designated location and response group settings for this device.
If you don't know your hostname, you can find it by right clicking your Little Green Button and choosing the About option.
In the resulting window, the hostname will show next to Using device:
In this example, the hostname is BAS-LAPTOP
You can also click the Technical Info button.
This will open another window, containing all the technical information for your button.
Towards the bottom, in the SESSION section, after Host: it will show you your hostname. In the case of the example below, the hostname is CLIENT-033