Well, this is actually a plug in, but it comes included with the toolset, so I've placed it here with the tutorials.
N.B. Invalid values in the effects editor can cause the toolset to crash, and the editor may delete any campaign directory contents, so do a backup before you start!
We're going to create just one effect to get started, but because I am far from being a dab hand with this editor, you can then use this experience to get comfortable with it:
Making your effects 1. First you need to get into the effects editor, so open up the toolset, and from the top menu, select 'Plugins', 'Visual Effects Editor'.
2. You can't actually see any existing effects, and it really is much easier to work from an existing one, so you will need to go into Windows Explorer or equivalent and find them all. They are stored in a set of zip files in the data folder of the game in a zip called NWN2_VFX (there is also an NWN2 Materials zip that might be interesting). Unzip the contents somewhere you can find it.
Effect 1: Cauldron Lights This will make a sort of slow spinning lights similar to the NWN dancing lights placeables, but slower and revolving.
1. We're going to make a particle effect using the 'fireflies' effect. Go to 'open' in the editor, and look in the folder FX_Ambient within your unzipped NWN2_VFX folder, and find fx_fireflies (set file type to pfx to make the search a bit easier, since you are using a particle effect)
2. In the properties of this effect, you're presented with a pretty meaningless bunch of stuff. You'll want to start with setting two of these first, so you can get the general 'feel' of your effect: FlowType