The guy that dumped it still makes money officially supporting it for Taito. If it where released publicly the arcades could get it themselves and they wouldn't need the tech.
I agree though, I hate when people hoard stuff. If it where up to me the publically available X2 library would be twice the size it is now.
I will probably be the one to release the majority of unreleased games when the time comes.
The FastIO I bought from you isn't the same FastIO required for DariusBurst. It was actually for some other "stuff". I really can't say much right now. Don't worry though, as long as I'm in the scene the public will eventually get everything when the time comes.