The modified doors worked very well but had to be changed back when it came time to sell the house. Most people, after all, would want privacy in their bedroom so a door with a window in it wouldn't be a good thing.
When I asked my dad if he could make a door for us that we could use to close off the basement so the cats wouldn't go down there when we didn't want them down there, he designed this special door for us. He used Plexiglas in it so that the light could still shine through and also so we can see if someone or something is on the other side of the door. It works well and I'm very happy with it. So is my cat, Spunky Doodle. The other day she followed me down there but didn't come up when I did. My husband didn't know she was down there and closed the door! When I was going to bed at 10:00, I saw her on the other side looking in patiently waiting for someone to open the door for her. Poor Spunky Doodle! (She wrote about this episode on her cat blog on http://karen.pnn.com (Cat Corner-MEOW) section.