As stated in the Document https://knowage-suite.readthedocs.io/en/7.2/functionalities-guide/birt-reporting/
"While developing a report, it is particularly useful to test it regularly. To this end, click on the Preview tab below the editor area.To revert back to the editor, just click on the Layout tab"
I could not find the preview tab to see the designed report. Please help.
there are only 4 tabs
Layout/Master Page/Script/XML Source