I've seen this one before in the main Med mod thread by preacherman involving the error message:-

MM2_TryMilitia,variable "MM2_TryMilitia#tmpLoc" and "noname" are of different type

There is no great problem here as it just falls out of the game but I always seem to be able to get back in from the desktop where the game was dumped so it's only a little annoying - this is the third consecutive turn that I've been dumped on the same message

But for all those skilled in debugging I've got about 8 cities now and a small stack of two barbarian archers wandering around looking for trouble. If you want more info I'll save the game as it is and give full details of who's where or what's going on

So where might be look for the cause???

The error message is also trigger at the time I settle my next city so somewhere along the line I suspect one of these variables has got corrupted during the game.