I use the step sequencer to make it happen
ill provide an example if and if not i can make it work
but as for the problem:
the step sequencer lets the original sound out during the portamentoing
it breaks the sound, because right now i can hear both sounds
the original, and the gliding
might just be something strange im doing, but worth checking out
the sound is awesome

http://fwsnet.net/mp3/hardsawwip.fxp