If your QS6 doesn't have a second footswitch input, you can buy a MIDI Solutions Footswitch controller and set it up for just about any MIDI message. You'd plug your FS 5U into it and the MDI Solutions device would plug in the MIDI out port on the QS6. If there are any buttons on the QS6 that send MIDI you can map the incremental patch command to it without the need for the above solution.
life thanks for the feedback. I managed to find another option from another user of the motu mkII828. The interface has a 1/4 in jack for punching in/out.
-MOTU Audio Setup>General>Enable Pedal>Pedal Down
-and assign Down Arrow by clicking on the 'Set' button and hitting the down arrow key on the laptop.-
-Plug your pedal into the 'Punch In/Out' jack on the back of the MOTU.
-When MainStage is open, you can go down through the patches.
-When it gets to the bottom it will cycle back to the top.
So this option is basically controlling the down arrow key on your laptop via the motu 828 using the fs-5u.
So if your concert/gig is set up to change patches incrementally, you just have to step on the fs-5u to switch to the next patch... Now the draw back, if ya hit it too many times, you are off and you gotta move back...can't do it with the fs-5u set up this way... but it is the same drawback with any hard/soft synth set up this way.
Now the Tech 21 MIDI Mouse Pedal is very cool...
but three times as expensive and it needs power. In this case, The midi mouse switches the patches on your keyboard, not controlling the down arrow on your laptop.
So different ways to do the same job. Since I already have a motu828 and the fs-5u, i'm going to stick to this method and give it a try for some time...we'll see how it goes.