The following steps are necessary to use your own map in ARK: Survival Evolved:
- Start Steam
- Launch the following URL in the web browser: steam://url/SteamWorkshopPage/346110 (Steam starts automatically)
- Alternative URL for the web browser: http://steamcommunity.com/app/346110/workshop/
- In the workshop, search for the map you wish to upload (you can subscribe to it if you want).
- Generally, mod developers will place the Mod ID into the description.
- Copy the mod ID
- Paste it into the Active Mod (IDs) field on your web interface under Settings > General
- Save changes
- Restart your server (this will start the download for the mod)
- Once your server is started, select the map from the dropdown menu in the web interface
- Once selected, the system should automatically fill in the Map start parameter
- Save your changes once again
- Restart your server.
The map should then be loaded onto your server!