First of all we'd like to request that you watch our installment video tutorial because this is basically 
a written explanation of what we recorded in the installment video

(How To Install video)
http://www.sonokinetic.net/products/classical/vivace/#video-tours

To clarify:

1) First you need to open Kontakt 5 (make sure your version of Kontakt is updated, check for updates through the Native Instruments Serivce Center)

*If you don't own a version of Kontakt 5 please download the free player from the the Native Instruments website. Here: http://www.native-instruments.com/#/en/products/producer/kontakt-5-player/

2) Open Kontakt , tap the 'library' tab and click on "add library":
kontakt.jpg
3) Vivace will appear in the library browser panel. To activate click 'activate:
activate.jpg
4) You've received your personal serial number in the Sonokinetic invoice you've received:
invoice.jpg
Use this number to activate your version of "Vivace:
fill in form.jpg