If I redownload and install the demo home page of Integrity 1 will it create a new separate page and not touch the home page that I'm working on? If I can do that I can use it as a guide for how the mobile versions of those sections are set up. Since I'm new to this theme and Cornerstone, as well as making separate mobile versions of sections, it would help to have that as a guide. I tried to use the Cornerstone code backup to make a new page as a guide, but that didn't work.
I do have some experience manipulating some code, but Cornerstone is so different, I was afraid to do that to replace what was missing.
FYI, I frequently get preview-loading errors while working and saving. I then have to reload the page and that's probably when the sections got lost. Based on input in other posts, I turned off Endurance Cache in the admin, as well as adjusting cache settings in Cloudflare as suggested in those posts. That fixed some things, but the errors continue. Just thought you should know for future updates.
In addition, hover text on theme icons, such as the Skeleton Mode, would be helpful.