Dev team here 🙂 I’ve checked out the website from lorrh (if not mistaken) and it looks like there’s more missing. There should be a code editor as well and uploading themes isn’t possible as well. I’ve put a fixed version of the theme in the media browser of your website. You can download it and upload it yourself. This fix makes sure that the theme settings are vivible to anyone who can login on your site. I’d also take a look at the permissions on your folders & files since uploading of themes and editing the code don’t work as well.
Let me know if the fixed version gives you the theme settings 🙂