I would start a new game, and constantly check for exactly when these extra files start showing up. Have a archive file (*.zip would probably be best) ready, and add the contents of the savegame/history folders, starting with before when the files show up, and going in a few turns. Send this in with a detailed explanation of your system (OS Version, service packs installed, etc.) to
malfador@malfador.com
Someone please correct me if Aaron is using a different address for bug reports...