FYI: I just took a turn in G&KMP in which the download file was 1,989, but the save file was 3,011 when I compared file sizes before submitting. So I canceled the Submit window, deleted the previous downloaded file (don't think this is required), manually downloaded a new file (don't think this is required), and re-took my turn. New save file was 1,989, so I submitted it. So the game moves on! I'm going to suggest to the GMR team that they implement file size checking in the client.