You can actually do a bank change with the Octa, but itās a bit of a hassle. After some trying, I managed to nail it down so that it worked consistently. (This is with a Nord Drum 2.)
You activate the bank change by changing parts in Octa. Before doing the part change, at the end of the previous pattern, send CC0 & CC32 one after another (adjacent steps). CC32 specifies the Bank number. The program number of the new bank is determined in the MIDI options of the new pattern. So, bank is set with CC in the pattern changing from, and program is set in the MIDI options of the pattern changing to. They have to use separate parts.
More details here:
You need to send CC0=0 and CC32=Bank number-1 on MIDI channel 10 (Nord drum 2 default) in the pattern. So CC0=0 CC32=0, for example, means that when switching parts, Nord Drum will switch to bank 1, program x. The program number will be determined by the program number in the MIDI options for that pattern in the Octatrack. So the bank change will be determined in two different locations, when doing a part change in the Octa.
Source patternās CC32 will point to destination patterns bank number.
Destination patternās program number will point to program number.
You need to define both for the bank/program change to work.
Sorry for a rambling post, ask me details if you need!