Arturia,
Please don't waste anybody's time with a Jupiter 8. The original paled in comparison to the Prophet (or the CS80 for that matter), as will any electronic copy of it you make. If you really want to do something that is really needed, and isn't just another stupid polyphonic analog emulation, please give us a simple monophonic (duophonic) Synthi-A/VCS3 engine that works and sounds like the original. That I would pay a couple hundred bucks for.
Moss