A few turns ago I had a naval fight near Isabella wherein I captured a stack of Spanish ships but only received one, and the others seemed to disappear. Later, Spanish ships started defecting to me at turn start, from the square in between the two Spanish ship stacks visible on the East of the map. I received the damaged caravel located there at the start of this turn. I believe this is also the square where the stack capture took place.
At this point, if I click on Paramaribo, load the 180 fur into the two carracks there, and move them or click "sail to Europe," the game freezes.
Also, not a bug report but a suggestion: the era requirements as you have them enforce a very specific style of play. In this game, you can see I am still stuck in the first era due to having built too many settlements, and it feels a bit awkward to go through almost all the buildings, without having real choices available. I would recommend changing the requirements about population, defenders, and rebel sentiment to only apply to three settlements rather than all of them, so you are not drastically penalized for having an additional settlement somewhere.