So I finally reach 25 % and could go to town.
After I visit it to do the new quests, I lost connection. I reconnect and all building and trees were doubled. Trees can be deleted, but to delete the building I have to buy them and this would be very expensive. The bug is only at the first district in town. A district I've bought after reconnecting havn't got this problems.
I tried to restart the web browser, to log off and cleared my cache and cookies.
Ubisoft Support Staff NCSA
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