The Historical discovery of America is impossible to perform.
When you start the 1492 New World scenario you already have a Christopher Columbus.
A little later on you get a pop-up asking you if you want to hire Christopher Columbus. If you say no, your original Christopher Columbus explorer stays on your generals list and is fully functional. If you say yes, you end up with a duplicate Christopher Columbus.
If you form an exploration expedition under the new system in early 1492, exploring the waters of Sevilla will reveal the Sargasso Sea, which almost gets you to where you need to be.
But there is no automatic expedition which gets you to San Salvador or to Hispaniola.
Instead you are left with a couple of ahistorical options that will end up with Columbus discovering the mouth of the Amazon.
(I am pleased to report that I did actually discover some terra incognita with one of the automated expeditions, so there's some improvement on that score).
I have nothing against alternative history. But in order to take it seriously and enjoy it, I have to believe that the model is capable of reproducing what actually happened, under the right circumstances. Not being able to discover San Salvador and Hispaniola on the first voyage goes a long ways towards killing the immersion for me. So I'm afraid this is a game breaker.
My sense is that the exploration problem would be fairly easy to fix. The first thing to do would be to include a discover San Salvador automated mission that essentially reduplicates Columbus' first voyage. The second thing would be to revisit what exploration missions are available, and to go over the list with a fine tooth comb. I'm assuming there is some kind of required sequence to the missions, and that sequence needs closer scrutiny, and perhaps some additions and restrictions. Maybe if you could only go off exploring in three directions at first, and depending on which direction you chose that would unlock new exploration options. That is sort of what is going on now, but the system is in need of tinkering and TLC.
And please do something about the two Cristobal Colons and the unamed explorer that you get when you opt for an extra explorer later on.