Had a quick play about this morning (didn't get a chance last night) and I did sort of get it working but I need to spend more time trying to perfect it, as it's a bit noisy especially with the synth attack at zero. THiS how I did it - I created an octoRex in place of a real guitar a Thor to convert the audio to cv/gate and a Malstrom to be our new guitar sound.
I plugged Rex (playing a guitar loop) L&R out to Thor audio in 1&2
Then plugged Thor's cv out 1 to Malstrom's seq control GATE - and cv out 2 to Malstrom's seq control CV
Then using Thor's matrix set first source to Audio In1 - amount to 50 - scale to MIDINote and amount to 31. (Some experimentation scope here with MIDINote/LastNote and amount)
With Thor's matrix again set the second Source to AudioIn2 - amount to 50 - Scale was set to LastGate and amount (worked best at) zero !
Now when the Rex plays you should be getting something sounding from the Malstrom.!! Maybe not quite what you expect but it's a quick experiment. And in all honesty, I not too sure it can be done now ! But let's try.. Maybe one of you can take this further and perfect it..
Also try different Malstrom sounds, try different amounts on Thor's matrix.. Lots of scope for experimenting.