This mode helps finding problems in your map. It shows a small dialog window with the checks you wish to perform. Press F4 in any classic mode to switch to this mode. Select the checks to perform and click the Start Analysis button. The problems that are found are displayed in a list. Click on of the problems to zoom in on the subject and show a description of the problem below the list. For some problems, buttons appear below the description that you can use to quickly fix the problem.