For sure Serato keeps it’s beat-grid info there. So if you changed a lot of beat grid info, that would be gone. Cue points is a different story. MiK can write cue points into the tags of a track. Then when imported the cue points show up. What I am not 100% sure about is if Serato then treats it as imported info and stores it in it’s own database too. Loops and other info goes into the database too I think.
You can always make a copy of said Serato folder and store it somewhere safely. Then delete the Serato folder, run a new import (or just with one or two playlists), as you import them they will be gridded.
Hopefully someone with more intimate knowledge of the Serato data in the Serato folder can shed some more light on this.
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