Can you tell me how to switch the trading back on? I'd like to test the scenario with it.
I was working on this scenario for a while, and just got back with it. For water trading, simply check "Enable Water Trade" for harbor, but it is going to slow the game down drastically. To get it to run on my slower laptop, I took at a bunch of the civilizations, and also eliminated a lot of cities, especially in Siberia, which did not exist until sometime in the 1800s or 1900s. I have Commercial Dock set for Water Trading, but that does take a while to get to as it becomes available with the Mercantilism advance. Not having harbors to trade is a real problem.
I have modified it quite a bit from the original, and for the Dutch Fluyt, I use the Schooner, restricted simply to the Dutch.
In the game I am in right now, I am at 1526AD in my modified game, and I am spending about 10 minutes while the AI does it thing and 30 seconds to a minute to do what I am doing. It is getting very tiresome, so I am looking at doing a lot more trimming of Barbarians and cities, and maybe some civilizations. In 1490, the Holy Roman Empire, Germany, and the Austrian Empire were all ruled by the same person, so that could be merged. However, that probably would make the combination over-powered. France, under Charles the Eighth was about to go blitzing into Italy, and reduce the Papal States to a shuttlecock between France and Spain.
I also am having problems with a lot of the European Powers turning to Blood Cult government, which is really weird. I set the Blood Cult government to basically worse than Despotism, and that got rid of that problem, but it sure messes up the Native American tribes.