The Wine config has to be set to Win XP. Then you should install IE 8 via the Crossover-Install Library including Adobe Flash and all Microsoft Packages that come with that install procecure. Afterwards you search for „Uplay“ in the Crossover-Software Library and start the installing of it. Continue the package install of some utils until the Uplay (Ubisoft Game Launcher) Installer starts. There you have to cancel implicit. Don't install Uplay as itself, that will be done by the Game. It is only necessary to provide the packages around. Now you can start the installer from Settlers 7 CD/DVD. After finished install start the Game and let download it an .exe-update-File for actually at the moment version 1.12 with 1,34 GB to C:\users\crossover\Temp
The downloader will fail the Autostart of the Update. Confirm the error message and start the downloaded .exe-File manually.
After the update you can start the game again and Ubisoft Game Launcher will popup. You have to login with your existing account where the serial is stored or to make a new account if the serial number of the Game was not used before. First time it's possible that UPlay will crash after login, but you can ignore that by starting the game once again.
Now Uplay is checkin' automatically into your account and wants to download past game results/scores and saves. That won't work. Just skip the according message and the game starts successful.