How can I change the Configuration Data URL for an App that is already published? Do I need to submit an update or can I just change the setting here and point to my external hosted version? I assume any new app downloads would still point here first? Also, is there a way to have it delivered by BT Server 2.0 that I already have up and running?

Check this doc out for a discussion of offline vs. online apps, and how to change the config file location: http://www.buzztouch.com/resources/Understanding_App_Refresh_and_Offline_Apps_v1.0.pdf Mark

I assume any new app downloads would still point here first until I publish an update to the App Store that uses the new URL? Also, is there a way to have my BuzzTouch.com v1.5 App's BT_Config file delivered by BT Server 2.0 that I already have up and running?

You can easily 'park' the configuration data that powers your app on your new 2.0 box. But, it's very very likely that trying to make dynamic changes to this data, using your new control panel, will break things. In other words, using an FTP program to upload a .txt file (the config data for your app) to a location on your server is entirely different than connecting it to the control panel and making dynamic changes. @GoNorthWest wrote a great article about this but for sure it takes some understanding to take maximum advantage of all the options ;-)