What is 'Bank Select Method' for

it specifies the way that bank numbers are selected via MIDI Bank_Select channel messages, CC#0 (MSB) and CC#32 (LSB), whether either one or both are necessary, recognized and/or reacted upon by the target MIDI instrument device, preceding to any subsequent Program_Change message :

• Normal (0) - both Bank_Select_MSB (CC#0) and _LSB (CC#32) are used to select the target bank number (7+7bit: bank number 0..16383);
• Bank MSB (1) - only Bank_Select_MSB (CC#0) is used (7bit: bank numbers 0..127 only);
• Bank LSB (2) - only Bank_Select_LSB (CC#32) is used (7bit: bank numbers 0..127 only);
• Patch (3) - no Bank_Select commands are used; target instrument does not recognize CC#0 or CC#32 as bank selection commands, have no notion of program/patch banks or assigned some other function than arcane bank selection;

This bank select method option is indeed a leftover from ancient times, namely from Cakewalk series of sequencers, from which qtractor was inspired more than a decade ago. It's also mainly suitable for (old) outboard gear, for where and when MIDI standards implementation varied from brand, model, version to version and production time. Yeah, the cheesy old eighties and nineties too.

hth.
cheers