Even though it's free you still have to get the license activated,you must install their license mgr application.
You're limited to what presets are on offer and can't save any edits.
Few third party libraries will work with the Player, though I am starting to see a few third party Kontakt libraries that will work with Kontakt Player.
I've downloaded them all (including the old Kore Player) and ended up deleting all of them, your mileage may vary.
I listened to Hatfield and the North at Rainbow. They were very wonderful and they made my heart a prisoner.