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If you the click the Next button you'll be presented with a screen that allows you to choose a starting template to use for the report. Generally the Blank Report is a suitable starting point. Note however that it does include the current date as part of the Master Page, so it's not entirely blank.
For this sample I'll just add a simple text box to the report since the intent here is to show how to create a BIRT report design, not how to generate a full blown BIRT report.
Once this report is saved the design file will then be available in the ...\weave\platform\workspace\reports directory and should be ready to register in Weave.
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