From Iron Realms Nexus Client Documentation
You may access the Import/Export options by opening the setting menu and clicking on the 'Import/Export' button. The settings menu may be accessed by clicking on the gear icon in the bottom right corner of the Nexus client.
The Import/Export options in the setting menu will allow you to backup all of your character settings on your own computer. You may also choose to restore your settings from previously made backups which we store on our servers.
If you have setting you have previously exported, you may revert to those by dragging the .nxs file from your computer into the "Import Settings" section.
You may restore settings that we periodically back up on our servers as well by clicking on the version you would like to use.