I just took the cover off the pedal and played with wires for a little bit. Here is what i have come up with. Let me note here that another of my qualms with the 707 is that all of the patch editing and sampling buttons can only be operated with your finger.
1. Twisting the hots from each pedal together means that any time you click either of them, both are sent to ground and the pedal goes into bypass, making it impossible to scroll through patches.
2. I decided to make a "lock" button using a non-momentary switch. I figure i will then be able to have a footswitch to connect and disconnect the two hots... thereby making either of the up/down pedals a dedicated bypass pedal when the "lock" is engaged.
3. The serial mouse that I was planning to canabalize for my cable only has 4 conductors (the connector has nine pins) so I can only bring one other "finger button" out to my external footswitch although i was planning on having all 6 patch editing, sampling and rythem (sp?) buttons be footswitchable.
i dunno where that leaves me, I am thinking that I might just use a parallel cable (looks like the computer side of a printer cable) between the external box and the pedal. That would by 25 conductors but it would be leaps and bounds better as far as pedal ease of use goes.
-Vadim