My Motif xs8 is connected to my computer through firewire and I am trying to use Motif XS Editor to control Motif xs for voice or parameter changes. After synchronizing Editor with Motif xs on Song Mode, I selected Classical Guitar, Old Blues, and Violin Sol for channel 1, 2, and 3, repectively, on Editor and the voices on the xs display changed as such. But the thing is, although I switch from Channel 1 to Channel 2 (Classical Guitar to Old Blues) on Editor, the actual voice is not changing. It is still Classical Guitar. On Motif xs display, the voice is still Classical Guitar. My question: even if I move back and forth between channels on Editor, do I still need to press the corresponding track buttons on Motif xs? Am I making myself understood?

It depends on how you are routing your signal and how you have the Editor configured and how you like to work.

Most people if recording with a computer or working with a computer work with LOCAL CONTROL set to OFF, this allows them to decide what PART is sounding by selecting it on the computer screen.

When Local Control is set to OFF, it matters not what channel you are transmitting ON, from the XS, the software application will determine what happens with routing of the MIDI data (that is, which of the PARTS will be sounding).

It is not clear from your post if you are just using the EDITOR in MIXING mode, whether you are sequencing in the computer, or in the XS… and of course, that could make a difference, as well.