The problem: "I have Kontakt Player as an active device, but no sound sets in the drop down menu." The manual fix for this requires that you get into and edit the Registry* so Sibelius 7 can see that the libraries are installed.
Remember, when using Sibelius 7 in 64-bit mode, Sibelius will only see 64-bit VST plugins.
EDIT: See second post below for a faster/safer method.
Step One:
Go to Start, click in the search field, type "regedit", hit Enter. That should get you to the Registry Editor.
Duplicate everything from
HKEY_LOCAL_MACHINE > SOFTWARE > Wow6432Node > Native Instruments > Content
to
HKEY_LOCAL_MACHINE > SOFTWARE > Native Instruments > Content
I use the word "duplicate" because that's what was used in the instructions I received. You will need to create the new entries from scratch since Windows doesn't allow the normal copy/paste function in the Registry.
From HKEY_LOCAL_MACHINE > SOFTWARE > Native Instruments > Content, right-click and choose New > String Value. Name the new entry to match what you're duplicating. Double-click that new item and fill in the Data field with "Virtual Drumline 2.5" - or whatever is needed.
I'd do a system restart at this point, then open Sibelius 7 and see if the sound sets display under a KP2/KP4 active device. If not, proceed to step two. I only had to do step one for the sound sets to show up.
Step Two (if necessary):
Duplicate the keys named after the libraries themselves and all of their sub-keys from
HKEY_LOCAL_MACHINE > Software > Wow6432Node > Native Instruments
to
HKEY_LOCAL_MACHINE > Software > Native Instruments
Yes, if you need to do this part, there may be a lot of them. Take your time and make sure that everything is copied correctly.
* The user is responsible for any modifications they make to the registry. If you don't feel comfortable doing this, then I suggest you wait for a patch that will do this for you (if NI or the like produces one). In the meantime, you can still continue to use Sibelius 6.