hello !
maybe i will write a stupid thing but...
i remembered when working with RackAfx that Will Pirkle created his rompler with integrated (hardcoded) samplepath to do this thing (bidirectionnal) and explained in his book that with streamed samples it's not possible. so it seems that Kontakt don't "stream" samples, but load them before in temp memory to do this.
sure it's a great function. but i prefer without but with streamed samples.
Not sure of this... Must have confirmation by someone else...