How screwed up are the rights to the Alpha Centauri series?

Have always wondered why we’ve never seen a sequel. Is it just a matter of the right people not getting together, or are the rights so bollixed up that it will never happen?

As an aside, does anyone know why GOG didn’t come out with Alien Crossfire when they released Alpha Centauri? That was sort of like going to your favorite Italian restaurant, sitting down for a delicious meal of pasta with red clam sauce…and there’s no clams in it. It still tastes good, but…

I actually saw that link a bit ago, which is what inspired me to ask the question here. Do they talk about the sequel/rights situation in the podcast?