/stage:import is the only time VDJTools will make changes to any of your files. In this case the database(s) that hold the track details, cue points and all other meta data VirtualDJ uses at runtime.
VDJTools will backup every file touched on import. Unlike a /backup, which backs up all files, during an import only the files changed are backed up. /restore however, works as expected. So if you do find an issue with the import, you can roll back with ease.
Once the import is complete, its best to verify everything went as planned.
Database Repair · Folders Repair · Playlists Repair · History Repair · Import