Once you install, use and like DJ-Suggester Light you can easily upgrade to Professional edition.
Steps to do the upgrade from Free to Pro
1. Purchase the DJ-Suggester subscription
2. go to My Account and find your license number
Now copy the license key and paste it in the DJ-Suggester plugin (1)
and click Go Professional (2).
Now the license key is entered and confirmed (see below screenshot [1])
and you can upgrade to Professional Edition (2)
after that you'll have Professional Edition installed: