set scene control to dual-Set one scene with portamento, one without.
Set sync so FM only controls the slave. Now you have cool weird harmonics, but the synth is in tune. set source 2 to VCO 2. You might want to play with the edge on VCO 2--closer to a sine wave. Might not. Try tuning VCO 2 an octave higher. Use dual so you can layer this with a more normal patch if you want.
sync pitch mod source--filter envelope. cool sound
Jimmy