The worst piece of drek this side of Pro Tools. Overpriced, the ridiculously cramped screen with tons of real estate wasted, you can't resize or even simply maximize that cramped screen, the ridiculous cobweb of file extensions, the lame and inconsistent file navigation, the weak customer service, the short shelf life (it's not long before simply having Kontakt is enough, you need a newer version for newer plugins, and can only get the free upgrade for minor upgrades), I could go on. And really this plugin within a plugin thing is stupid in the first place. It's a shame that so many plugins were written just to appease this archaic software sewage, which is the ONLY reason to get it. Fortunately I there are a ton of great plugins which don't require it, and few if any sample libraries do anymore, so I'll never waste money on it (I'm only familiar with due to a friend having it and quickly realized how happy I was that I never bought it).
Dear dizzyfingers, it can be the file how it's designed (no bread and butter here, all patches are made with several layers to have a complex movement) or the way you play it back in Kontakt 5, the higher the key you play the more it sounds jittery... try to start from C3, and follow the note "try lower keys" for more subtle and soft soundscapes. Cheers.