@anonymous_user_1267f45c - the question about what the recommendations are around accounts for testing in the Creators Program is not one I know the answer to. Sounds like a good one to take directly to the Creators Program folks.
@Sparkash - as you’ve discovered our current implementation doesn’t really support offline Live sign-in on Win10. If you’d like to change that then you’ll need to crack open the EraAdapter project. If you look at ShowAccountPickerAsync in SystemUI.cpp it relies on a successful call to GetUserProfileAsync in order to return a valid user. This is to ensure that it can populate the user’s DisplayInfo member with data that is a reasonable match for Xbox One, but it’s also where offline breaks down. If your project can do without some of the data in DisplayInfo then you could implement a return path that doesn’t rely on the GetUserProfileAsync call succeeding.