Sadly there was no backup. I'm starting from scratchas said above, one or more of your files has been damaged.
the best way to repair it would be using files from a backup instead of from a new project.
in all cases, there is a reason why your files were damaged, and you'll need to find out that reason to prevent a repeat. So after you repaired the projects as good as possible, come back here and we'll help you to check what damaged your project.
Ok thanks, the good part is I was only 4 days in and can get back there relatively fast. Still a kick in the ballseveryone who has some computer experience usually tells everyone else to always make backups, but sadly most people have to lose at least one big project before they believe that. And that isn't restricted to hobby people or RM's, I know an architectural bureau that lost all data of a 80K$ work one day before it was due.
that said, you still have to find out what happened.
the most common causes are
1) power failure on the computer
2) shutdown failure on windows
3) cloudsync failure if you're using a cloud on your data.
3 is the reason why we tell people not to have their work projects stored in a cloudsync'ed folder, that has already destroyed dozens of projects beccause the RPG-Makers handle their projects like a database and not like a regular filesaving program. And the databasing process is at special risk when cloudsync'ing.