Please clarify what do you mean:
- If you mean the option is not Selected, this is not normal, and it seems you don't have the latest version of the installer.
- If you mean the option is not editable, so it's grayed out, but SELECTED, it's entirely normal, and it's made like this to clarify both that the Navdata is Enabled, but also you are not supposed to turn if off, so it's not editable.
If you really want to, you can disable it ( we don't suggest doing it ), but it must be done by manually editing the Couatl_MSFS.ini file. From the Installer interface, it's always Enabled and can't be Disabled.
