5. Somebody mind explaining me about the concept of Worst Enemy and why it's so important? I think I fail to understand that.
8. Message is "Tang Taizong is willing to trade Literature" but when I check on him, he said no it can't be done eventhough Literature is selectable for trade ._.
This existed in BTS. Essentially, each computer AI civ will pick one other civ to be their "worst enemy". I think it's the one who they have the worst relations with. It can change during the game, and the BUG interface will alert you when this happens. You receive a diplomacy hit if you trade with a civ's worst enemy.
BUG alerts you when it's possible for a civ to trade a technology to you. It doesn't mean that they're willing to make the trade though. If you go to the foreign advisor tech tab then it will show you the techs that they will actually trade.
So if Korea is worst enemy with China, will I get diplomatic penalty with China if I traded with Korea before I met China like before?
Fixed the load/save bug. All stored Python data should now be correctly retrieved again once you reload a save after restarting the game.
WARNING: The next commit will break savegame compatibility once again. Not that it matters much as they are broken without this fix anyway.
I consider this the reason for most of the reported bugs during the last days, and won't check whether it was the actual reason. So please report everything again if you come across the problem after updating to this revision (588).