Firstly if you still have access to your old computer then the easiest way to transfer your data is using our
Backup/Restore functionality - this will make an exact copy of your database and will be much quicker than re-importing everything.
If you can't make a backup and don't already have one then...
Duplicates do mean that the hands were already in the database, but if you stopped the first import before it completed then it's possible that not all of the hands were imported. Did you let the second attempt to import run to completion? If not, there could be hands towards the end which weren't imported. It's also possible that tournament detection wasn't completed if you stopped the import process early, which would mean that some of the tournaments weren't detected as the correct types (and may be why you're seeing different numbers of tournaments when you filter).
If you remove all filters do you have less hands/tournaments than previously? If you don't have as many hands as before you'll need to make sure that all of your files were imported.
If you do have as many hands then you may need to force detection for your tournaments to make sure they were all detected - you can do that via the
Edit Tournament Results window. Since you have so many I'd suggest doing this in batches to avoid tying PT4 up for too long at once as tournament detection can take some time depending on the tournament types.