I will hesitantly say that I think we're in business. I just re-uploaded our map for this game (changing all the file names), and tried starting a game with it (MapTester4 for those interested), and this time it did start correctly, and sent out turns files like it did in the good old days
I will test it again to make sure, but if that test goes ok as well, then I think we are on safer ground to go for a third attempt by re-uploading Pretenders again. (as we've sent some scouts out this time to test the land

)