Hi Gigantoad, I think I have found a solution. I was looking for a portable live setup where the harmonizer is used both as an AD/DA and FX box. I came up with a routing setup that provides the following features:
DA: FW1 inputs 1/2 straight to Analog out 1/2 (for monitoring or main outputs of computer).
AD: Analog inputs 3/4 straight to FW1 out 3/4 (for recording analog gear).
FX: Four channels of firewire IO available for DSP processing. For example in two discrete send/return pairs, each taking their own DSP.
I tested it, and it works. I'll try to upload pictures, but that seems to be a bit of a black magic here. 😉