Simon 5 is coming soon!
Simon version 5 is currently in beta testing. It is a massive update, introducing a much-requested feature: syncing the Simon data between multiple Macs, plus a Simon Status service, a Link Checker filter, improved Find filter, iMessage and Speak Error notifiers, a new app icon, and much more.
Important: please note that Simon 5 requires a minimum of macOS 10.12 (Sierra), and will be a paid upgrade from Simon 4 after the beta. Purchasers since September 1, 2020 automatically get a version 5 license (that also works in previous versions).
Re: Simon crashed and now I'm missing data
I'm sorry to hear that. I haven't heard of data loss like that before, but I suppose if the machine lost power at the precise wrong time, when the file was being saved, it could happen. Would be a major fluke, though: the data is written out in a way that should avoid that possibility.
Anyway, the data is stored in the ~/Library/Application Support/Dejal/Simon folder. You could perhaps revert this folder from a backup to get the data back, though of course you'd lose any changes you've made since then.