Hi,
I think it's not very clear from the doc.
You first select the bank once.
Then, use program changes to trigger a preset load from the selected bank.
Chosing the bank is done through regular CC.
If you want the first bank of combo :
Send 1 to CC#0 (Combo)
Send 0 to CC#32 (Combo bank number).
Then sending program change will load combo from the first bank of your combo bank.
But i have no idea how to send that from the octatrack.
And i still haven't looked at what Lokki did exactly for program change, so i cannot comment
Xavier