This tool imports flags into your USUM save.
1. Load the program
2. Load up your decrypted non-corrupted USUM save
(decrypted non-corrupted USUM save basically means a USUM save that loads in PKHeX)
3. Select an option within the drop down box
(note, these set of event flags were obtained from a save that backed up the point in time explained in the text of the drop down box)
4. Click Inject
5. Open the save in PKHeX, then save in PKHeX, to fix the checksum.
Unless there's any major game-breaking bug (excluding users not fixing the checksums properly), I have no intention of fixing/updating this.
While the text in the drop down box contains a lot of misspellings, this should be something users can figure out..
Also, if you can't load the save after the edit, and you're sure you fixed the checksum, check out this tutorial: