I didn't want to go too long without an update on this. I've done some significant work on the software (PC side) to configure the instrument. The way this will work is:

1. Define all the play settings with this application.
2. Connect MIDI-OUT from your PC to MIDI-IN on MIDI Hero.
3. Software sends MIDI SysEx message containing new settings to MIDI Hero, which then saves them to EEPROM in a bank of presets.
4. Presets loaded from EEPROM when the instrument is actually used to perform - swap from acoustic to electric on the fly, or between chord sets, etc.

Here's a screenshot of the program.

Still a work-in-progress, but much of the functionality is there. Don't be alarmed by the Windows 7 UI - the whole thing is being written in... wait for it... FreePascal using the Lazarus IDE. So that makes it easily cross-platform when I release the code later.

This is my first time using Pascal / Delphi / etc. Can definitely see why it was the beginner language back in the day, but I'm treating it more like a cross-platform VB6 and it seems like a good fit.