Supbscript and superscript shortcodes not working

I’m having trouble getting a number of the shortcodes to work. I’m specifically interested in [subscript] and [superscript].
I have added the two shortcodes to the whitelist-plugin. But still no luck.
Other shortcodes like [quote] and [spoiler] works fine.
I’m wondering if has to do with either of the following two problems:

1)
[code]Warning: Invalid argument supplied for foreach() in /home/ashome08/public_html/<domain>/wp-content/plugins/bbcode-deluxe/bbcode-admin.php on line 15[/code]
2)
[code]REMOTE_HOST - Your web server must be configured to create this variable. For instance, Apache needs HostnameLookups On in httpd.conf.[/code]

I’m not sure why this latter is necessary? At any rate: It’s impossible for us on our siteground account, as the HostnameLookups is a share setting for all of the sites. This problem must apply to most shared-hosted users.