Guys, I think I figured out the problem by myself...
I didn't copy the tracks to the external driver INSIDE RekordBox 3.2 on my old MacBook BEFORE exporting the master database because it didn't said so in the tutorial about this that I read.... The tutorial written by Pulse entitled: "How To: Move your rekordbox (3.2+) database to an external drive / sync between computers"
Maybe its a good idea to add that info...
Now I did it all over again, just like the tutorial mentioned above explained but BEFORE exporting master database I copied everything INSIDE RekordBox to the same external driver that will be the NEW master database, and voila'; IT WORKED!
Thank GOD!
Thanks a lot!
Cheers,
TZ