I think you're confused about what maximizer does. All it does is remove the border around a windowed-mode WoW window and let you specify the exact size/location. So instead of having a 1024x768 window with a border and titlebar, you can make a 1000x400 window with no border.

It does not let you control the alt from the main's screen. You'd still have to click on the other window to bring it into focus to do anything on it.