How about assigning another note playing row ( say, "Base Octave - 1" ) to numerical keys above letter keys - they used currently to set an octave, which can be done with keypad. If use also '-' and '=' keys we'll get full octave range (or don't touch important '=' and use 'Shift-Minus' for "Base Octave B" ).
I mean only to add commands from "Base Octave -1 C" to "Base Octave B" to pattern editor so user may choose to redefine keys or leave as is.
EDIT: Dupe of this request (http://forum.openmpt.org/index.php?topic=3232.0).
I'm sorry to say this, but I don't understand anything of what you've just written... :(
You press '1' - you hear the note.
It's one octave lower than what you hear when you press 'Q'.
And you change octave with '/' and '*' keys.
Sorry, but I still don't get it. Can you describe your function by telling a story where you use it and point out the reason why its usefull? I might then understand it.
Goto ModPlug Options Setup, goto "Keyboard" tab, select the category "Pattern Editor - Note Col" and there you should see commands "Base Octave C" binded to 'Q' key, "Base Octave C#" binded to 'W', "Base Octave D" binded to 'E', "Base Octave D#" and so on.
I want to add there another 12 such commands: "Base Octave -1 C", "Base Octave -1 C#", ... , "Base Octave -1 G#", "Base Octave A", "Base Octave A#", "Base Octave B".
Sorry for those bad descriptions.
Aaaaaaaaaaaaaah :) Makes sense now... :)