[ashlar]

With versions being implemented in a similar manner to Sets. Will the play button play the default version while other versions are access from the dialog?

As far as I understand it and as far as it has been discussed, it should work like this, using keyboard standard commands.

Once the "cursor" highlights a movie:

Pressing Enter goes "into" the movie versions and you'll be shown the different, labeled, versions available (Extended, Standard, UHD, etc.), in the same way as going "into" a Movie Set shows you the different movies in that set.

Pressing P (for Play) will playback the default version of a movie with multiple versions.

While pressing C (Context Menu) will allow you to then select "Manage..." and from there access the Movie Versions dialog window, where you'll be able to manage all the different configurations.