Hi ezb, great to have another hardware synth buff on board ;)
When you create a preset on Midi Designer and recall it, all values as they stand will be sent to the target hardware and hopefully, if it can cope with this chunk of data at the speed it is transmitted, will change the current parameters of your hardware to that of the Midi Designer Preset. Very cool I think!
Midi Designer will not however 'listen' to a patch dump or specific SYSex data from your target hardware and then distribute that data to the correct or mirror parameter as far as I am aware. It may sound easy enough and is when considered as MIDI CC but it seems to me that there would be many implications with this method that make it rather more complex when dealing with SYSex than first meets the eye :)
You may have to make concessions on your layout within the limitations of MD but you are also providing a great editor to the community that can be updated as MD evolves with time.
Either way, thanks for your efforts and research so far! It sounds like owners of the CS6X are in for a treat thanks to you. The community is still tiny here but growing and the 'Dev team' is smaller than anyone would believe and yet still beyond dedicated to it's development.
Keep at it!!