BioWare has released patch 1.64 beta 3. This version is not supported by BioWare, nor by Atari, and there will be a patch to revert to version 1.62 prior to installing the final version of the patch. All modules created or saved with this version of the toolset are tagged as requiring 1.63 version of the game.

See the release note (http://nwn.bioware.com/support/winclient_beta.html) at BioWare.