Yup the CALD topics have been very inactive, some of us are mostly on the tulpa forum that’s linked a page ago. I for one am currently trying to get back into LDing, but first things first, so I’m still working on DR at the moment. My mind characters/tulpas/whatever are still all there and I’m not planning on neglecting them any time soon. I’ve never had any actual success with CALD itself, but the characters can be of a big help when it comes to improving your awareness or giving you suggestions à la MILD.
Concerning the writer thing: Yes, I’ve also come to the conclusion that a good bunch of writers/artists could definitely have a MC/tulpa without realizing it. Sometimes you stumble upon an interview with a writer who talks about how his characters are basically the ones telling him the story, or you might come across a comic where the artist’s character interacts with the artist just like any other real person would do. It’s difficult to differentiate though between such characters and the CALD characters, and one would have to ask the artist to be sure about it. I can only say so much, there seem to be a lot more people with talking, self-aware characters in their head than you’d think.
Occasionally I do have (very awesome) dreams with my characters in them, and one of my main goals in each LD is to meet them. After all, meeting your character in a (lucid) dream is as difficult or as easy as summoning any other person.