Well, I am sorry for this glitch as well as for the delay in posting a response. (I was at a birthday party today). I see that this is the pesky "immortal Roman leader" bug. I had put a test in my development code for this but I couldn't duplicate the problem. Then I forgot to change it to a more benign form in the public beta.
Now that this has happened, I can see exactly what the problem is. This will be corrected in a second public beta that I will get out there as quickly as I can. I need to test it a little more and then I will have to consult with Andrew and Erik. They're the ones who prepare and release the final installer for you. I'll have to see what their schedule is.
Thanks for reporting this, and of course I am sorry for the inconvenience. As a work-around, you can turn off the "Verbose AI" (to avoid boredom) and then refrain from using the Escape Key (or the mouse, etc.) to shorten the AI's movements on the main map. It is only one specific stage that has a problem - when an army is moving by land and is subject to attrition. If that stage is "escaped" and the army didn't lose any units at all then this problem will occur.
Of course this work-around is only temporary. There is nothing wrong with shortening the AI's moves on the game map. Or, at least, there shouldn't be anything wrong with it.
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