Edit: I moved this to the proper area

I've had some more occurences of a bug I thought I was wrong about before.  In a recent game, a CTD was caused whenever I chose Housing as a research advancement.  I kept loading my saved games and autosaves from the same world before the research advancement and every time housing was given as a choice, I chose it, and it crashed to desktop.

Next (keep in mind, this is during repeated trials of loading the same world) I tried choosing other research advancements, it did not cause CTD.  I hypothesized that it might be caused by having huts in queue when getting the Housing advancement, but I still got a CTD when I removed them from my construction queues.

Next, I razed all of my huts and chose Housing: no CTD, trying it about a half dozen times, whether I had huts in queue or not.

So my guess is: there might be some error when existing huts are turned into houses.  But it doesn't always happen, just during some games.  I had two cities, maybe that was the cause, I'll see if I can figure out anything more sure.