Thank you for your replies. The suggestion that I describe the bug to see if anyone might be willing to fix it led me to try it myself, and lo and behold I think I managed it.
The problem was that it wasn't letting infantry units move after the first turn in which they moved, and the note that came up said they're unable to blitz. It was like the count of territories they were moving through wasn't being reset. Then in the AAA release notes I saw that for 188.8.131.52 “resetUnitState” was changed to “resetUnitStateAtEnd” and “resetUnitStateAtStart” so I opened the hood and replaced the old string with one of the new ones and it seems to work.
Thank you again for your suggestions.