I have the Vo17 how i can add the Vo18? Do i really have to download all the Game again?
I have the Vo17 how i can add the Vo18?
Upgrade your game from version 0.17 to 0.18.x.
Do i really have to download all the Game again?
No.
There is patch for PC version 0.17 that upgrades it to 0.18. It is available at the Downloads section like the other downloads.
You do not mention what platform you are using, so I can not advice on how the patching might work. The patch download is a zip file, inside it is Readme-file that tells how to do the patching.