I see...I figured it had to be some kinda "insider" thing.
So let me see if I have this straight...you attached a second ProThrot to the daisy-chain via an added Female DB-15 and activated some additional (normally un-assigned) key-matrix lines by adding a few switching/blocking diodes to a 1st Gen circuit board.
I'm assuming that later gen circuit boards do not have the extra available lines, so this is more-or-less a one-off mod.
Too bad, I was hoping I might be able to add some extra functionality. Still, it's something to think on.
You wouldn't happen to still have a circuit diagram or layout would you?
Thx
CptA