Password protected help center in widget
At this moment it is not possible to add a password protected help center in a widget. You can choose the channel, but the widget remains empty. This particular widget is only available in a password protected environment so I know that people that see this widget are allowed to see the articles.
I see in the widget code that you have to add window.trengo.key, so maybe add something like window.trengo.passwordprotected = 'Iknowanditsokay'; can do the trick ;-)