Try to find the double-arrow icon in all that mess - if you can see it, right-click on/under it to change modes. if not , you will have to edit planeshift.cfg, with any text editor, to have three lines, near the end of the file look like this:
PlaneShift.GUI.ControlWindow.CurrentStyle = 3
PlaneShift.GUI.ControlWindow.Width = 780
PlaneShift.GUI.ControlWindow.Height = 56