You can upload Rust saves and userdata directly through Clanforge, here's how:
1. Log in to Clanforge
2. Click on your Server Name, or the small, blue "Manage" button to the right of the page
3. Open the World tab below the server info
4. Select your world file to upload from your local machine direct to your server. It must be in either .zip or tar.gz format! The archive must contain the .sav file. It may also contain the userdata folder.
5. Enter anything into the Description box
6. Click Upload
7. Once uploaded, open the backups dropdown inside of the World tab and select the most recent one (the one you uploaded).
8. Click on "Restore a Backup" to restore it. This will restart the server to apply it.