URGENT: site broken after update and then uploading from backup

So I’ve already posted on the many issues plaguing my website www.backpacksadbridges.com following the latest update. As the site had become unusable, I attempted to reupload from a back-up made a few days earlier. However, the site is still not functioning properly, on the front end, above the header is a list of error messages linked to unretrieved elements such as “Cornerstone_Element_Orchestrator::add | Failed to add element: classic. Class ‘CSE_Classic’ not found” (see screenshot for full list)

On the back end, I can’t access /wp-Admin anymore, as I get the following message:
“Fatal error: Call to undefined function wp_cache_get() in /home/backpa11/public_html/wp-includes/option.php on line 1117”

What I suspect, although not being an expert I’m not sure, may be causing these errors is:
-I created one post and modified one embedded video using V2 elements
-Since that back-up I re-uploaded, I installed Cloudfare on my site, modifying my DNS

How can I fix this and get a functioning site while I wait for the new X and Cornerstone to be really backwards compatible with my previous site?

Thank you

SOLVED To get back to my previous version and get it all working, I had to go into the FTP, uninstall cornerstone, w3tc cache and wpml. I deleted the content that used classic v2 elements and then reinstall wpml and w3tc… It was a bit of a hassle, but it works again. Hopefully you will come out with a truly backwards-compatible update to x and cornerstone soon…

Glad to hear it’s sorted.

Cheers!