If I have 3 windows opened in the same application (e.g Google Chrome) I get this in the Unity Bar:

OK, that's good and expected. If I click that, it will Scale the windows that belong to that application, like this:

Great! That's what I want to achieve more often by using hot corners. I did that with TopLeft and Scale All Windows, like this:

How can I achieve the scale of only the application windows (like Chrome) with a hot corner (like TopRight)? I've already tried "Initiate Window Picker for Window Group" but it doesn't work.

Am I missing something? Using Ubuntu 12.04 and the Scale / Scale Addons plugins.