By default only two environments are available to connect with(Production and Sandbox).
In collaboration it can be possible to connect with ‘Acceptance' or even ‘Development'. For this you have to enable the Admin Mode. This can be done by running the following function via Anonymous Apex:
Social25.Ctrl_Config.toggleAdminMode();
After running this function you have to refresh the page and ‘Acceptance' and ‘Development' will also be visible.