To request a diagnostic report, click on the plus sign in the right corner. A pop up will appear, check the boxes next to the type of report you would like to request. If you would like all the reports, click on the check/uncheck all button. The reports will then be generated and added to the list. When the report is added to the list you can click on the report name or the blue arrow to download the report.
To check on the status of the report you can check the queue task.