On the front page, scroll down to move from the map, to the charting, to the data table and finally the image editor. if scroll is not working while you are viewing the map, it is because the mouse wheel is tied to the zoom on the map. Use the browser scrollbar in this situation, or the navigation bar.
The top bar is used to move between the sections of the IMS. Click on any of the named sections to go to that part of the application.
The left-hand bar is used to open search menus, and where necessary jump to the relevant sections.