I came very very Close to a CV OCC deity standard Brazil, however I did some very big mistakes and was unlucky with the setup.
I did get Artemis (Archery free Tech like turn 3), Hanging gardern (which don't give great enginner Points anymore).
I'm pretty certain that's incorrect. It's not listed in the online Civilopedia, but that's hardly free from errors (Berserkers at Metal Casting indeed). Unless Artemis produces more GE points than I realised, my engineer bar was climbing too fast for the Gardens not to be producing. I'll check when I reload my ongoing Ethiopia game (started a Hun game to test out the infamous warmonger penalties).
Korea Went Culture and hyperteched to education, would have gotten the Chaple if I did not rush it with enginner which was a very big mistake because I could have saved it for the Porslin Tower (RA is basicly how I could be like 3rd in Tech).
Doesn't sound like a mistake to me, if you were going for culture victory in OCC (quite apart from the Chapel's main effect, you need those art slots). Even in isolation Sistine Chapel is arguably the better Wonder, though both are very good.
Then I Went for S method, which was very stupid, I should have gone straight for archaeology to get both the wonders and as many artifacts I could have in my city.
I'd agree with that - though OCC hits a problem in that regard because you can't gold-buy archaeologists and have to produce them all individually. You do want it for the wonder and the slots, though.
In the end I got only 2 artifacts and no wonder.
Someone in your game actually took Exploration?
However I did get Broadway and its theming bonus and the Eiffel Tower by a beline and Oxford, I should have used Oxford to get to Architecure and rushed the Porslin Tower with Enginner, or rushed the Uffzie.
Again I'd disagree. On one city you need Broadway more than you need Uffizi - you get art slots from a museum, the Hermitage, the palace, and most of the tourism Wonders. Music you only get from an Opera House and a Broadcast Tower, and each only has one slot. Though I'll grant that musicians are more useful than artists for their secondary ability. And while I'd rather have The Louvre than Eiffel, I'd rather have Eiffel than Uffizi (EDIT: France specifically is an exception, since it doubles the theming bonus - with the Aesthetics finisher - to 12, the same as Eiffel, and gives you an Artist plus art slots).
The Problem in the end was that one Civ Korea did have so many Wonder that I could not produce enought tourism to beat them.
I think the answer to this in culture games, if they're the only outstanding obstacle, is to wipe them out. This isn't vanilla/G&K any more, and cultural victory does not demand or particularly reward peaceful play, beyond the fact that OCC makes it hard to build an army - then, that's what militaristic city-states are for. You only have to have cultural superiority over surviving civs. To be successful at culture, you need to be close to tech leader anyway, so should have an advanced army.
Build NC, Tech to Theology, Open Piety and Get its Wonder (6 faith per turn + add in temple and shrine can be the difference of getting a GM in the end or not)
That wonder seams very safe compared to say Hagia Sophia which go very fast, In my game I could have gotten this to say the least.
At least on Immortal, Djenne is more favoured by the AI in my experience than Hagia Sophia. The main reason to prioritise Djenne over Sophia is that it's simply better. The AI doesn't seem to much favour Religious Art (which is probably a follower belief you'll want), so it's not critical to speedily enhance your religion.
Tech to Education rushby University If I can, otherwise Build it and Prebuild Oxford to one turn.
If you go down the full Piety route for the Reformation belief, you can try for Jesuit Education. Since the most limiting factor when playing OCC is production slots, as you're almost continually putting out Wonders, being able to faith-buy universities and research labs with the faith you aren't using for pagodas (since you can have at most one, Pagodas etc. are pretty pointless for OCC) can be valuable.
Here is probably the most Important decision, Tech Acustics and hope to get the Chaple, could rush with enginner or Tech to Printing Press, A Tech the Ai seams to be slow on getting.
Printing Press Wonders can be chain rushed giving both more Great Writer Slots which are harder to find then Great Art slots and 25% to Great People Generation.
You're right, that is a tough call. If you don't get Great Library you do rather need The Globe, and it's not around for long in most games. At the same time the Tower boost to GP production is less valuable since you don't have all that many great work slots anyway, and Sistine Chapel culture seems to count as coming from the Wonder for hotel purposes - I had upwards of 300 tourism in my OCC game without ever getting to The Internet, and much of that was from Sistine Chapel, Alhambra (be sure not to forget this one - since you only have one city, it's basically a second Chapel) and Hermitage (if NWs count for hotels).
On balance I'd go the Acoustics route - that also lets you pick up Alhambra on the way.
Then there are the thing about Great Musicans, If I wait to get them and get alot of tourism I could very quickly get a few very powerful Musicans, however doing so will mean less Great Works and Less Culture, meaning slower Policies.
What are you doing with all that faith, again? You don't want to stall on GM production just to rush them at the end, partly because tourism very early builds up and can lead you to become influential with some civs before ever hitting the Modern Era, and partly because it's the Great Works and other tourism sources you have that are used to calculate the benefit of the GM - if you skimp on them and miss out 20+ GWM tourism, that's 200 tourism less you're spamming every time you sacrifice a GM.
I'd produce GMs as soon and often as possible, and faith buy any others. You can always save a few up between Opera House and Broadcast Tower when you can't otherwise use them.