Hi jfrancis -
The banner you describe is the normal game header that should be at the top of the window. The video image should be visible below this black banner. The video window and scoring panels can be moved up and down using the windows scroll bar along the right edge of your window.
You might want to change the overall zoom you have set for your browser. This is what my screen looks like for normal play.
Notice that there is an up/down scroll bar for the chatbox and another for the whole page.
Hope that helps.