Ok, welwell I think I figured this problem out.....but not without some investigative reporting.Seems the 'Multivalue' parameter type available for use in widgets has been renamed to Multivalue:string.....this is at least as far as the GP example for 'Extract Data' is concerned. This syntax was not updated in the GeoprocessingWidget_ExtractData.xml provided in the 3.0 sample viewer, at least the last time I checked.To find the correct syntax I had to load the sample 3.0 into the app builder. Before that I made the 'config-all' XML file the main config file so I could see the GP widget. I then changed the GP task for the widget to the one that is in the GeoprocessingWidget_ExtractData.xml file. Lo and behold, in the list of parameters, the type said multivalue:string. I plugged that into my custom GP widget XML and voila, I could see my list of layers to select for download. Now if I can get back the 'jobfailed' error I will be good to go.I tried the GP widgets on the sample page here http://resources.arcgis.com/en/help/flex-viewer/live/index.html?config=apps/config-geoprocessing.xml, and the extract data task does not work...I do feel a bit satisfied that it was not my syntax that was the issue.Anyway, I hope this information helps others trying to cobble together their own functionality based on the compiled viewer. What is frustrating is that there seems to be no reference as to what is possible in widgets (and I am talking GP specific for now) unless there happens to be a sample XML. And when the sample is flawed, you spend days banging your head. I am sure I am not the only person out there that is limited to using the compiled viewer to make web apps that can be customized as much as possible. More references, examples, etc. would be helpful, as would making sure the samples provided work 😉Charlene