Unfortunately, it may still be caused by an AI faction's queued item. You might want to run the game with "-ian" switch, load up the 1204 savegame, and see what the other factions are doing. I think Novgorod would be shift+7 or shift+8, I would check to see what they have on the queues and what they units/buildings they already have.

Apart from that, can you upload your unit/build prod files somewhere? And your early.txt, if you have changed it.