The Extension Panel has two different "faces". On the one hand the buttons shown in the main window in section "The Main Window" are displayed. On the other hand the buttons are shown below. This depends on the setting of the "Scan Expert" switch in the General section of the preferences.
For a further description of the other "face" see "The Main Window" description.
Scan Box
Gives you an idea of the currently set values of Resolution and Mode.