When I go to update my game with a new, much better edited version, I click "Edit this listing", then "upload a new file", then I attach the new updated version, but I get this message- "Invalid file type - please use 'Publish' (from the Tools menu) to create a .quest file"

I don't see a tools menu in the update options. I don't understand how to update with my new revised version...

When I asked around a month ago if I could update my game with a new version and still keep the reviews, ratings, and comments I had, I was told I could, so I'm apparently just missing something here.

It's the Tools menu in the offline editor. There you can create a new .quest file.

Thank you! I did that, then it let me upload the updated version no problem.