It's always good to review what has been done in the past, so this section contains examples, both good and bad, of puzzles in NWN1, NWN2, and similar games.
Mikar posted a FAQ for all puzzles in NWN1: Hordes of the Underdark. It's a great reference for when you are planning our your own puzzles in NWN2.
I made this FAQ because I'm seeing so many questions about the puzzles in HOTU in this forum. I hope that this FAQ will reduce the numbers of threads where people ask for advice on the puzzles.
Check it out:
http://nwn.bioware.com/forums/viewtopic.html?topic=319245&forum=82