In the heading row you select or enter a report number. If you have entered a new report number then you should also enter a name. If you have selected an existing report number, you will automatically see the name of the report.
There is also a check box where you can select which report that should be the default report in the system. Save when you have entered a new report number and name.
In the Report definition tab you define the VAT report and in the VAT control tab you register control numbers for VAT controls.