I've just gone through the rules, and no rule changes found as far as i can see.
The most interesting is the back of the pamflet with the explanation of how it works with other expansions.
Most are very straight forward, but these i found interesting (though i dont see them as rule changes):
- You can only place a bridge on a Circus tile (10th expansion) if there are no meeple artists on it
- You can place the Mayor in a castle, but it won't get any points (as there's no shield in the castle)
- Cloisters and Shrines with a vineyard generate the extra points to a castle as well.
- Castle gives a farm with a pig 5 points
- Castles generate 1 point more than other cities when a farm with a farmer or barn is scored (as well as when a farmer is scored when a barn is placed)
- Castles do not count as cities when counting cities for the King
- Meeples in a castle receive points for a Circus tent scoring (as long as the castle is in the surrounding tiles)
- A meeple pyramid does not activate scoring for a castle
- If you place a tile with a bazaar on a project with your builder, you pick the tiles for the double turn after the bazaar round.
- If, during the bazaar round, you place a dragon tile, the dragon moves. After that, the bazaar continues