Chapter 8 Lightmaps Question

Chapter 8 deals with creating Lightmaps for Light Baking. After following the steps and 'Baking' lighting, no lightmaps are generated. After a little research I realize I should probably set one of my actual lights 'Baking' setting to 'Baked' instead of 'Realtime'. So first I set my primary Directional light to 'Baked' setting. This generates lightmaps but removes the window cookie from the scene and now incorrectly lights the entire scene. So then I switched the Environment Lighting -> Ambient GI setting to Baked. This appears more correct. The tutorial never discusses switching any lights to 'Baked' from 'Realtime' though, so I'm just guessing. Does anybody know for sure what's missing; what I'm supposed to be doing to properly light the scene? (*Note: I'm using Unity 5.50f3 Personal.)