scook
Io be clear, you are using the same program on both synths.
I tried the same Dim Pro piano patches in Dim Pro and Rapture Pro. I also tried a number of other Rapture Pro piano, organ, synth and bass patches. Every single one of them honored my Nektar sustain pedal on my P6. I was surprised when it worked on the synth patches, to be honest.
So? NTF.