Tom,
You can use a 6 pedal or 13 pedal with the x1 to do pitch bend. If you go to any of the switches you can assign the pedal to be glide, and the amount of glide is programable to go either up or down. I do this all the time to create a pedal steel effect of a trombine slide effect. I'm not at my store right now, but I've never tried assigning a sustain pedal only to a different effect. I'm not sure if you can do it, but most of my customers want to use the 6 pedal board because it can be assigned to almost anything the keyboard can do.
George Kaye