itch.io

Ooh, that's an interesting error. It looks like it has to do with us doing a version update of Ren'py between version 2.0 and 2.5. One of the base files is different between versions, and it's causing the conflict. 

Did you delete the old build before downloading the new one? If not, I'd try deleting everything and then downloading the new build fresh (there should be a button taking you back to the download page at the top of the Obscura web page), as something may have happened with the new files and old files merging to cause this. 

If you want to back-up your saves first, it only takes a minute to dive into the files. It looks like you're using the Mac version, in which case you should* be able to go into the Obscura.app file, then go Contents > Resources > autorun > game > saves, and just copy the files in there and paste them somewhere else (I use a back-up folder in my documents, but as long as they're elsewhere it doesn't matter where). After deleting the old build and downloading the new one, you can paste your files back into the saves folder (same path). If there's no save folder, just start a new game and save on the first screen, then you can replace any files in the save folder with your original saves.

*I unfortunately have no experience with Macs, so if there's issues with these instructions I'd recommend looking up info about backing up Ren'py saves on Mac, you'll definitely find better troubleshooting than I can offer.