After quite a bit of frustration, the engine now supports multithreading. I thought it would be one of those things that it would take months to figure out. Thankfully, however, threading wasn't that scary. It just took two solid nights of frustrating failures.
But that's over now, and launching multithreaded jobs is sleek and easy. The polygonization algorithm (Crawling Cubes), which was my main motivation for exploring multithreading, received around a 20 to 25% speed up after making it multithreaded. Unfortunately, that's not as good as I was expecting (I thought using two cores would make it somewhere in the vicinity of twice as fast...). Still, any improvement to procedural mesh algorithms is one that I'm most certainly willing to take, considering how pivotal these algorithms will be in ANR.
I'm also working on advanced metaballs that include rotation, and should have some progress to report in that field (get it?) sooner than later.