If you can locate Compatibility Files, that's where you should find your saved designs. It's fairly easy to find on Windows 7, but it looks as if you're on Windows 8 or newer, so I'm unable to give you a detailed map of how to get there. However, it should somehow be accessible after you click on your RollerCoaster Tycoon 2 folder.

If you can locate Compatibility Files, that's where you should find your saved designs. It's fairly easy to find on Windows 7, but it looks as if you're on Windows 8 or newer, so I'm unable to give you a detailed map of how to get there. However, it should somehow be accessible after you click on your RollerCoaster Tycoon 2 folder.

Found it, Windows 10 hides the files by default now so you have to manually search them which is really backwards. Anyway, cheers!