I have found that, when attempting to save shader settings with the GUI, only the first listed shader is saved to the XML. Furthermore, that shader does not activate in NWN, nor does it appear as selected the next time the GUI is activated, and when the latter is again closed, even the previously saved shader is removed from the XML. All non-shader related settings are persistent from one GUI activation to the next, and they appear to function properly in-game. Just a thought, but I wonder whether it's possible that the GUI is saving shader settings with a syntax that differs from the one read by the GUI (and the system as a whole)? BTW, using Chronepsis with Patch 0.2.3.0.
In addition to the above, I have since noticed that when NWShader is active, I cannot preview my character model during character creation (i.e. the model preview shows only the black background). I have confirmed that upon removing the six DLLs from the NWN folder, I am again able to properly preview a new character's appearance.