Obviously, brand loyalty is a powerful marketing advantage and should be exploited. I think calling the game just TORN and integrating the BIS name clearly in the graphical logo would be as effective as the compound name. It is the wonderful Forgotten Realms setting that keeps people coming back, not its inclusion in the games' or books' title . Icewind Dale Trilogy. This naming convention also raises questions about the title for the inevitable sequel or expansion pack.
Common practice is to name it after the game with an additional subtitle.
Yet, these issues are not the worst thing about the name. Its biggest problem is that it isn't unique. Torn is a simple word, used everyday. The word is so common I can't even pick up Natalie Imbruglia's hit single Torn. It sounds like a great backdrop for an RPG as Sundering suggests an epic, cataclysmic event.