Hi agaro,
I will try to give you some answers, but first of all...
...please don't worry. We need feedback - especially critical feedback. Feel free to say what you're thinking.
Yes, they are sold at 80% of the European price but that is the gross amount.
You get a message when a rival city has achieved the Legendary Culture-status. That is the highest level of cultural expansion a city can achieve (100000 produced Liberty Bells in this city). Except the extension of the cultural borders there is no effect.
I will try to give you some answers, but first of all...
I would also like to emphasize that I am very respectful and in awe of all the work you've done. It is the nature of change that we end up talking about the small few things we differ on, rather than the large number of things that you've done that are great. I think I should say this because perhaps my comments are being translated into German and I hope they do not come out as impolite.
...please don't worry. We need feedback - especially critical feedback. Feel free to say what you're thinking.

- Are you able to explain the victory conditions? Ive never understood them even in Vanilla.
- Turn Limit (in Vanilla "Europe"): This victory condition is an (additional) option which limits the number of turns in the game. You have to declare independence within a certain number of turns (in Vanilla 300/in TAC 900 turns on normal gamespeed) otherwise the game will be lost. If you choose this option, you should choose it additional to the victory condition "Independence". In TAC this option is useless, so it will be removed in the upcoming final release.
- Score Victory after Turn Limit (in Vanilla "Time"): Limits the number of turns in the game. If no party reaches a victory in another condition after a certain number of turns, the party with the highest score will win.
- Independence: After you declared your independence you have to defeat every royal (land-)unit on the map.
- Domination: You have to hold a large land mass and a large number of the population on the map.
- Industrialisation: You have to produce a huge number of goods within one turn.
- With the Customs House do your lost goods still get taxed?
Yes, they are sold at 80% of the European price but that is the gross amount.
At one point I heard a hissing sound and saw a message that a Spanish AI city had been upgraded to some form of elite status. How did they achieve this and did they get any benefit?
You get a message when a rival city has achieved the Legendary Culture-status. That is the highest level of cultural expansion a city can achieve (100000 produced Liberty Bells in this city). Except the extension of the cultural borders there is no effect.