Trouble opening up an old Scrivener file

I have a weird issue. I wrote a novel in 2017 on an old version of Scrivener for Windows. I now have Scrivener 3 for Mac, but I saved all of my old files from my old computer. I’m trying to open that old project, and sometimes I can get the project to actually open, but all of the chapter folders just have empty documents with no text, just a scene title or even the first sentence of the scene that was originally there. There are like four recovered documents in a separate folder, but not even close to the rest of the project.

When I try to open another copy of the project, it lets me know it’s an old file and needs to be updated. When I click okay, I get an error message that says “The update has been cancelled because there was an error when trying to create a backup of the project. Please check that there is sufficient space on your hard drive.”

I definitely have room on my hard drive, I’m not even close to maxing out on storage.

This project is so so important to me and I would do anything to be able to just open and read the original files, even if I can’t edit them. Is there anything I can do? I still have the .scriv files and a backup version but I’m not having much luck opening these old files on my new version. I don’t have my old computer anymore or else I’d try that. I’m pretty desperate so I thought it was at least worth asking if you have any advice.