Can't create a cross application data map with multi-dimension mapping

Summary:

I'm trying to create a cross application data map, which requires one dimension in the source to map to two dimensions in the target. I've set up the connection, and created the basic data map. But once I enter the Map Dimension screen, after successfully putting the mapping dimension members in, when I click "Done", it does nothing and eventually pops up with a message "this page isn't responding". I can Wait or Exit Page. If I click "Wait", it does the same thing. If I click "Exit Page", it closed the map without saving and then I get an