It seems that when using DisplayRootViewFor<T>(), the RegisterNavigationService (on PrepareViewFirst) method is not called and you end up with null passed in for the INavigationService.
This didn't happen on the previous version.
Comments: I'm a little annoyed by the breaking change. Previously to this change I used the ViewModel first approach and NavigationService was configured for me. My application worked perfectly fine. I cannot register the existing Frame, caliburn crashes trying to register it manually when configuring the container. So I've updated my code to be View first just to solve the problem and not have to do extra work to handle navigation. I had a look and I can't find any decent documentation on creating my own conductor.
This didn't happen on the previous version.
Comments: I'm a little annoyed by the breaking change. Previously to this change I used the ViewModel first approach and NavigationService was configured for me. My application worked perfectly fine. I cannot register the existing Frame, caliburn crashes trying to register it manually when configuring the container. So I've updated my code to be View first just to solve the problem and not have to do extra work to handle navigation. I had a look and I can't find any decent documentation on creating my own conductor.