I spent a lot of time at the wonderful wiki trying to see if this is possible. I downloaded the HD 500 file with the basic midi commands and even created the alt. version that addresses all 8 effects.
But I am stumped about program changes. On the HD 500 I can be on any patch and use the Scroll UP / Down buttons to go thru the patches. Is it possible in the Browser Mode to scroll up / down thru the various profiles / rigs stored there? This is not for a performance situation, just and alternative way to scroll instead of using the scroll or page buttons.
I love the idea of using the HD 500 as a controller, because when using the Variax (and cable) it can also power the guitar. No batteries needed.
Im also feeling at a loss about implementing the wah pedal. Read lots of different posts that gave me a little headache