Topic: Hack/Fix for using Yamaha FC3 sustain pedal non-Yamaha Expression
I figured out a Hack/Fix for using a Yamaha FC3 sustain pedal through my non-Yamaha keyboard Expression controller input (a Nektar GXP 88 in this case). 
The Nektar Footswitch input only works with On/Off switch-type pedals. 
The Expression input works, but the Control Change info was reversed/inverted/upside down. Yes, I could set Pianoteq Controller 64 range to 1.00 and 0 which works for Pianoteq itself, but in my DAW all the info was reversed/inverted so if I sent the MIDI file to anyone else it would be wrong. 
I opened up my pedal and reversed the red and black wires--unsoldered them and re-soldered them in the swapped positions, leaving the white wire in the center alone. Voila! I put my Nektar on the Exp type 2 setting to work with Yamaha pedals. 
If you have questions, let me know. If I don't get notified by this site (I haven't posted anything before so I don't know how that works), you can email me at scott@scottwillispiano.com
I use the new version 7 NY Steinway D on my recordings, tweaked a little, mastered with multiband compression, an extra reverb, limiter, EQ to just cut any excess low frequencies, but pretty much stock.