Well I bit the bullet and got a copy of Kontakt 5 and Torch! It works fine in standalone mode but SHS6 cannot find it as a VST. I've added it to the VST Scan Folders. It's in the same NI folder as my B4 II Hammond and Guitar Rig 3 both of which both show up in the "Insert soft synths" and "vstplug-ins" option. I've also run scan VST folders and rescanned failed Plug-ins but no success. Kontakt is a exe file and doesn't seem to have a .dll associated with it. Is that the problem?? Any thoughts anyone?

Could it be something like...you need to configure Kontakt as a synth in the Plug-in Manager?? I'm not sure, but it could be...

Sorted! Finger trouble on my part.
Having failed miserably to sort it out, I decided to delete Kontakt 5 and start again. What I had failed to notice was a tick box during the installation which is required if you want to use Kontakt as a VST. Once I ticked it and re-installed it, it appeared as a VST in Sonar 6.
 
Thanks for taking the time to reply though..