The main character can now crawl. It sounds like a minor thing, but now that the character is actually an entity in the cellular system, the system has to be able to resize entites, check to make sure there's room, and things like that. The analogue in the platforming system is all those problems with handling wall embeds and ejects, which is one of the trickiest parts of programming a platformer, so trading these problems, which are now solved pretty much, for those, which I never could get to work right in the prototype's dynamic world with a sprite overlaid, is a good trade I think.
I'm going to have to modify the display engine now to display multiple possible actor states. After that, more inventory work, then maybe actually putting in new entity types, like growing plants, the beginnings of an ecosystem, and other actors.