Hello. I (and a number of other producers) are having exactly the same problem. As highlighted in the comments on Dan Keen’s video about Soft String Spurs https://www.youtube.com/watch?v=zAXKVbZ4nG4&t=2s
I only have the paid versions of Kontakt 5, Kontakt 6 and Komplete Kontrol installed on my system. I don’t have the free Kontakt player installed.
This seems to be common issue on several piano book libraries, which is a shame as there is some excellent content on here.
I have reached out to Dan Keen, the developer of Soft String Spurs and he’s kindly agreed to look into this issue.
I have also contacted Native instruments, but history sadly shows that their customer service leaves a lot to be desired.
Any help or guidance gratefully received.