Based on your screenshot of the issue, the website resources like images and CSS are not loaded. Cornerstone does not do that. There’s highly likely an underlying issue with your WordPress and/or server setup that breaks Cornerstone.
There are a lot of factors that could hinder the resources of your site from loading. Below is a list of some of those factors.
Factor 1: Having an index.html inside the folder where you installed WordPress.
Solution: Have your web host delete the said file
Factor 2: CORS
Solution: Please read here: https://theme.co/docs/font-awesome-icon-issues
Factor 3: Redirects
Solution: Contact your web host to disable all redirects in your site and also reset your htaccess file.
If none of that helps and as requested previously, please provide the following info in a Secure Note.
- WordPress Login URL
- Admin level username and password
- URL of the page you’re editing
- FTP or cPanel access (ask your web host in case your not familiar with this)