If you are working with data that is still being developed, you may find it useful to use a design-time feed. For example, if the server developer is still finalizing the database behind your XML data file, you can use a test version of the file to design your page separately from the database development.
To use a design-time feed, you must complete the Testing Server category of the Site Definition dialog box.
To obtain a design-time feed, browse to locate
the file and click OK. (You arrive at this dialog box by clicking
the link in the Define Spry Data Set dialog box.)