First of all you need the SteamCMD. You can download it here:
https://steamcdn-a.akamaihd.net/client/installer/steamcmd.zip

Now you need to execute this file.

First, we need to create a folder for our server, which we can do with the following command:
This will create a folder with the name "craftopia_ds" and it will put in the files in this folder.

And now we can login.

Now you can start the download with:

If the download was sucessful, you have to type
in the console to close the SteamCMD.

The best option is to create a .bat file in your "craftopia_ds" folder (e.g. RUN.bat)
Edit the .bat file with following code:

To stop the server, open the server console and use "CTRL+C"

You can find your "ServerSetting.ini" file in your "craftopia_ds" folder.

If you want to use a password, you need to change
to

And with
you can choose a password. Keep in mind, that the password can only be numbers at this time!

To convert your Singleplayer world into Multiplayer you have to open the following folder:

This is your singleplayer savegame, you can now copy this into your serverfolder!
Copy everything beside the "steam_autocloud.vdf" file!

Now go into "ServerSetting.ini" and change

into the name you put your world's name, mine for example would be:

I can not see my server / No one can connect to my server
Please make sure, that you have opened all the required ports in your router. If the everything is set correctly, but the problem still occurs, please contact your internet provider.
Or look for your router model here:
https://portforward.com/router.htm

Is there another way instead of opening the ports?
Yes, you can also host your server through a VPN network like "Hamachi". Of course only the people in the VPN network will be able to join the server then.
If forwarding your ports doesn´t work, please contact your ISP, i won´t be able to help you.

How can i change my server port?
Just edit the "ServerSetting.ini" file the option "port=8787"

The SteamCMD download failed! What should I do now?
Mostly you just need to retry the download, then the problem should be fixed.

How do I update my server?
Just open the SteamCMD and login again, then retry the Step "Downloading the files" it will be checked which files need to be updated.

To automate these steps to setup/upgrade a server, i created a tool, the group can be founde here:
http://steamproxy.com/groups/ServerTool

The tool itself is hosted on Github, which can be found here:
https://github.com/Zeromix9/ServerTool

I hope, that will help you in the future!

If you like, you are also welcome to leave a small donation.
https://paypal.me/Zeromix