To install mods please follow this step by step guide:
1. Click "Configuration Files" button.
2. Locate "GameUserSettings ini" And Click "Configuration Editor".
3. Locate "Mod ID's To Load" (AKA Active Mods) and enter each Mod ID separated by commas. (Note: No spaces between mod id's and no comma after the last mod). Example List of Mods: 895711211,1382008288
4. Click Save (Which can be located at the top left).
5. Go back to the control panel home page (Click Game Services inside the left hand side navigation menu).
6. Click "Install Mods" button and wait for the console window to inform you the operation has been completed, then close the popup console window.
7. You can now start your server and your mods will be running.