On the website, the file to download will be a reasonably small executable (less than 40 MB) instead of the installshield of 1.7 GB. Once downloaded, you will launch it and it will propose to download around 610 MB of files, which are needed to play on the Ruins of Silan. Once installed, RoS would use around 3.3 GB of space on your hard disk.

You will also have the possibility to download the rest of the game while you are playing on RoS. You would have around 800 MB to download (mainland and Ring). The files will auto-extract in your Ryzom folder that will use around 6.5 GB of space once Ryzom is fully installed.

All these downloads will be resumable.