Obsidian Entertainment's Rob McGinnis, Tony Evans, and Matthew Rorie field questions about Neverwinter Nights 2: Storm of Zehir in a new interview at Thieves-Guild.net.
Which feature in SoZ was the most difficult to implement and why?
RM: We had quite a few features that caused some difficulty. The problematic things are always those things that require global changes or touch the faction system. The overland map, the party conversation system and various AI improvements probably top the list of troublesome features.
The overland map requires many new systems and changes to old systems. It changes the gameplay of Neverwinter Nights quite a bit. Nathaniel Chapman put a lot of thought into the overland map to make sure it would be easily accessible to the modding and persistent world community, and I think everyone will like the results. You no longer see the world through a microscope, moving from one little area to the next. Now, entire regions and countries can come into play. The world itself becomes an actor in your story.
The party conversation system was difficult because it pushes the engine in a direction it wasn't originally meant to go. I think the end result was well worth the difficulty, though. The party conversation system really helps to make the game more party focused. You aren't skulking through dungeons and interacting with the various denizens of Samarach alone; you have friends along to help get you out of any trouble - or maybe it was to help get you into trouble. I always get those two mixed up.