You can use Note on/off, program change or control change (CC).
I’d recommend just using a note on for simplicity.
So a note on, middle c, half velocity in hex would be 0x90 0x3C 0x3F
In the Avantis, you do not need the 0x to denote hex, so just 90 3C 3F
Custom midi control of Qlab using the soft keys on Avantis.
Go: F0,7F,00,02,01,01,F7
stop: F0,7F,00,02,01,08,F7
next: F0,7F,00,02,01,13,F7
back: F0,7F,00,02,01,14,F7