Here is the official thread for my new project, "Terracell". The name "Terracell" is a combination of the names Terragen and Lunarcell and pretty clearly illustrates its design goal: to be the Lunarcell for Terragen. In other words, a randomizable, modifiable, and user-friendly detailed planet-maker in Terragen 2. With the TGD file (to be released later), users will be able to create as great a variety of planets as they can with Lunarcell, but with the added realism and 3d-control granted by the powerful Terragen 2 software. Among these benefits are the ability to add multiple and colored light sources, render realistically from the surface of the planet as well as orbit, and deform the planet using displacement in ways Lunarcell could never dream of, among other things. I also plan on eventually including a basic, configurable ring later on, for those who want to easily create ringed planets.
Keep an eye on this thread for future updates.
Edit: Added a demo pic from version 0.24. Also, when there is a version to release, I will edit it into this message, so that it is at the top of the thread and easy to find. I may also put a link to it in my sig.