One of the new features of Qtractor is a Sys Ex message that can be sent when a MIDI track with an assigned instrument is connected to its output in the connections window.
Cool, this way I can use my Korg X3 in combination mode or sequencer mode, and keep that choice remembered in the song's Qtractor session.
Here's how I've set it up:
First go to "view" > "buses" in Qtractor's main window.
Then choose MIDI master bus, your instrument and hit the Sys Ex button.
Now hit "Export" to save as .syx file.
I exported a "set-combination-mode.syx" and a "set-sequencer-mode.syx", so when I start a new Qtractor session and use the Korg-x3, all I have to do is open the right syx file, hit "Add" & "Ok" and the next time I open this Session, the Korg will jump to the right mode at the making of the connection.