Since a few years now, new shortcuts were added automatically to existing key maps, rendering this topic and its instructions kinda obsolete.
However, there has been one big deficiency in OpenMPT that has bothered me for years, especially since it was not there in the ole ModPlug Tracker: Note mappings are not layout-independent. What does that mean? Imagine you have a German (QWERTZ) or French (AZERTY) layout. The keymap saves e.g. "Base octave C is mapped to key Q". That works in most (ISO and US) layouts, however on the French keyboard, the letter Q is in a completely different place. In the case of the German keyboard, Z and Y are swapped, so the two notes mapped to those two keys are swapped as well. Things like this are why OpenMPT ships with several key maps which pretty much only differ in their note mappings.
I have now found a way to kinda return to the way ModPlug Tracker did this: In addition to "virtual key codes", which OpenMPT used until now, it also stores a "scan code" for note keys, which tells it where on the keyboard this key is located. This way, note keys are completely independent of how the letters are arranged on the keyboard. The default key map now has its keys stored as scan codes, but I cannot do this for the user-provided key maps, because how they should be interpreted depends on the original layout they were designed for.
So once again I am asking everyone who contributed a key map to grab r7363 or later from https://buildbot.openmpt.org/builds/
(it's still compiling, so it should be up in a few hours), load your keymap and then simply re-save it to a file
, and then post the new file here so that I can replace it. This way, the note keys in your file will also work for other people who use a different layout.