or you just set Kontakt to receive incoming MIDI from Max in Kontakt preferencies and then set Max midiout to Kontakt.
the vst way is more straightforward but if new to this it may require a little more time.
have a look at this patch, it receives info from a makenote, but before it you must append a channel, though not know if you are experienced with that. in case ask
ah, if you don't use Kontakt as a vst, you can only send MIDI messages to it, but not receive the audio unless you use something like Soundflower (that i don't suggest because i experienced audio crackles coming from clock drifts) o jack (which i suggest)