Small fix and change for alternate locales

There are two small changes, the first of which (on line 945) is required - `$cleaned_sysem_locale` becoming `$cleaned_system_locale` - whereas the second (on line 956) is a workaround for showing `"" was not found in our list of valid locales.` when none is specified. I'm proposing that only because it confused me when debugging my locale issues.