i may have already mentioned this, but name any user voices (and styles if you plan to add custom styles) with numbers at the start. e.g. 001_Piano 002_Dark_Piano and so on

That way it wont mess your registrations up if you add a new sound or style that is alphabetically lower than the voices already saved. Ketrons registrations don't link to actual files, but to locations.

As an example if your first user voice in the Trumpet section is called "Harry_James" and you have a registration that loads the voice, adding a new user voice called "Alison_Balsom" will save 'before' the Harry_James trumpet. Now your registration will link to Alison_Balsom instead. Adding the numbers in front stops this from happening.