I'm have the same problem. I've been using arcGIS Explorer online to build my queries for my ArcGIS online maps for mobile devices. Now that we can't use ArcGIS Explorer Online to open version 2.0 AGO maps I can't create queries. Does anyone know of a workaround?
The way I'm doing it currently is to create the maps in Explorer Online including the queries and then save them when they're done. The only issue with this is any work that needs to be done on the map must be done in Explorer. The moment you save the map in ArcGIS Online it can't be opened in Explorer any longer.
It works for now until we get the ability change between locators in the Explorer app. That's the only reason we're still using the old green app over the Explorer app at this point. Hope that helps!