Like your work so far looks great!
You say that a librarian is not possible, how about this. You perform a full backup of the KPA, load it into your app, the app allows you to browse and edit rigs, change settings and modify other info, import/export rigs etc. then gives you the option to export as a new backup file that you can restore into your KPA via USB? Just a thought....
Could work?
Spence