At present I'm still working on the 2nd level of Undermountain. This weekend I did more fleshing out of the east area, building some more rubbish placeables to scatter around and laying down visual effects, lights, and sounds to create the proper environment. When I build these areas, I try to make them feel like small parts of a much larger dungeon, so there are blocked off corridors due to open pits or metal gratings, platforms with doors on the other side of a gap, and so forth. I was tempted to add another area to the mix, but for right now I decided to stay focused on the existing content. This version of undermountain is generally dank and gloomy with islands of light being provided by torches, braziers, fires, and magic. It's much darker than the original HotU dungeon, which seemed excessively bright. Hopefully that won't be to much of an issue for the players. There's always magic glowing rings available at the start of the game.
While implementing the cleric Linu's recruitment location, I discovered that there is a whole separate track of party member conversations that I need to add. A number of the script elements for this game are buried in the standard stock scripts, so it's been a matter of burrowing through the code and finding out where it leads. In this case, it turns out the companion conversations used prior to being recruited are separate from the party member conversations; a switch that is handled in one of the stock henchmen include files. These separate conversations are probably going to take another week or so to finish, but they are needed since they handle the cases where you alienate companions.
There are quite a few differences between how companions are managed in NWN and NWN2. These have led me, for example, to some content cuts from the conversations, since you won't need to ask your party members to do things like cast spells or change their primary class. (I'm actually setting the condition to gc_false for those branches, just in case.) I need to spend some time figuring out what I need to convert from the old henchmen scripts to the standard NWN2 companion scripts, which could take extensive work as I'm finding out. Plus, now that most of the party members can be recruited, I need to set up the party management interface in place of the NWN method. I'm planning to make it a NWN2 OC style party management. Most of the conversations will be OC style, rather than SoZ, and use the NWN conversation interface.
There's at least one element of this area that I haven't figured out yet -- an invisible entity in one of the rooms. I'll need to dig through the various triggers to see how that is activated.