The SetName NWScript function should be included in NWN2 [1]. Currently however, this function does not exist in the pre-order toolset

// Set the name of oObject.
// - oObject: the object for which you are changing the name (a creature, placeable, item, or door).
// - sNewName: the new name that the object will use.
// Note: SetName() does not work on player objects.
//       Setting an object's name to "" will make the object
//       revert to using the name it had originally before any
//       SetName() calls were made on the object.
void SetName(object oObject, string sNewName="")

WARNING: This function is missing from NWN2 and thus any script which is imported that uses this function will fail to compile