Restoring a backup
You need administrator rights, because the service has to stop.
1. Stop Kustos. In an elevated PowerShell:
Wait for it to actually stop before continuing — Stop-Service can return while the process is still shutting down.
2. Move the current database aside — do not delete it. If the restore is not what you wanted, this is the only way back.
3. Copy the backup into place. Pick the one you want from backups\ and copy it — copy, do not move, so the backup survives.
4. Delete the -wal and -shm files. This is the step that matters.
Those two files belong to the database you just moved aside, not to the one you restored. Leaving them is how a restore appears to work and then does not: at best SQLite ignores them, at worst you get a database that is part old and part new with nothing to tell you which parts.
5. Start Kustos.
6. Check it came up. Open Kustos and look at a screen whose data you know changed, such as Activity. The Backups list will look the same as before: it reads the files in backups\, not the database. If Kustos does not answer at all, the service log in %ProgramData%\Kustos\logs\ says why.