I'm afraid that I don't know any tricks to get back those missing events.
A personal rule that I follow is to keep multiple backups of my mods at different points during their construction. I number them to keep from getting confused, and keep them handy until I have a fully playtested version released.
It's also now my habit to have all my hacking done before I start putting in events. I keep story notes in little real-life notebooks while I finish the hacking, --that way I don't lose any good ideas or details. Usually, I only have some Pics, Sprites, and Combat Icons left to add or change by the time I start putting events into dungeons.
I think most FRUAuthors have lost significant work in computer crashes or other unexpected calamities. I know I have. My experience was so painful that I could never bring myself to begin my lost mod again. Now I take plenty of precautions against such misfortunes.
But please forgive me if this post sounds like something Captain Hindsight might've written.