Click the Red circular button 'x' glyphred exit button to close 'eE' EscapeE iconEscapeE windows and the 'ee' EEview iconEEview Control panel.
Click the Square white button 'X' glyphwhite exit button to close the EEview Control panel but leave the EscapeE windows open.

Note that if you have selected an RTIMAGE Compare option then the RTIMAGE remain open.