Bwahahahaha, welcome to my world!
Well, no, not really, but this was happening on my singlecore in the previous version. I'm about 2 hours away from downloading 0.85 so I'll get to testing it soon, maybe even verify how it works on the singlecore compared to the older version. You could check to see if the time continues to be that long on maps with low density of monsters and resources and with different AI levels. I found no conclusive evidence that it has a noticeable effect, but you may have more luck.
LE: I've gotten about 200 turns in and so far nothing has lasted more than 4-5 seconds, and that's when I was speeding trough the turns.