Jos,
When you load the new OS file, you have to also load the PROGRAMV.BIN file. Copy this file into the ROOT directory. Turn on the MIDIJAY and as soon as screen comes on (before LOGO), press and hold down together the Playlist buttons 0,1,2, & 7. Follow screen prompts. Let me know if you are missing this file from your ROOT DIRECTORY.
As for the voice parameters, you can change them and store wherever you like...(see previous email above on manual location for this)... however to reload the original, you will have to repeat the process above to load the PROGRAMV.BIN file with the original settings.
Thanks,
AJ