1) Install Visual C++ Redistributable 2005 and 2008 into a fresh Win2k bottle, using CXGames 8.0 installer.2) Install DirectX 9 Legacy, using CXGames 8.0 installer (this step may be unnecessary -- see step 3).
3) Install NWN2 OC. Both .NET 2.0 and DirectX 9 should install successfully after the main install.
4) Patch up to the most recent 1.23 (to legally shake off the DRM).
I didn't touch the registry or do any magic with the DLLs. The key was the win2k bottle. If you use a winxp bottle, all sorts of things don't install properly.
Once I had this working properly, I then did:
5) Install MotB and SoZ.
6) Patch again up to 1.23 (since SoZ drops you back to 1.20).
For patching (steps 4 and 6), use the manual patcher and patch files available on the NWN Vault, at:
http://nwvault.ign.com/View.php?view=NWN2Tools.Detail&id=12 (for the patcher)
http://nwvault.ign.com/View.php?view=NWN2Articles.Detail&id=230#english (for the patch files)
You may need this link: http://nwvault.ign.com/fms/Download.php?id=133235 if you need but can't locate nwn2_pcx2_english_from1211549_to1221586 in the list.
It is possible using the manual patcher to queue the patch files, so you can do the whole thing in a batch. If you intend to install MotB and/or SoZ, don't bother with step 4: you'll need to patch again at step 6 anyway.