Wendersnaven.com (a resource for nwn2 builders)

In this thread, puiwaihin was trying to figure out why his invisible creature couldn't cast spells at the PCs. In the end they figured out that anything that is invisible or hidden can't do it.

jackyo123  suggested making the creatures super small instead.

Check it out here:
http://nwn2forums.bioware.com/forums/viewtopic.html?topic=576056&forum=114