[LVL ED] FATAL ERROR: Could not load world file 'custom_stories

[Romulator]

Well, the map itself is a format known as XML. As such, opening it up with a text editor might allow you to navigate through to see if there are issues, but if you're not careful, could simply ruin your map beyond repair.

If you upload your map somewhere, I don't mind taking a look for you to see if I can try to recover some of it.

how are you going to proceed in order to retrieve as much of the data as possible. Are you gonna use the method of the text editor that you mentioned?

Yep. You certainly won't be able to open it with the level editor to fix it :p