A few months ago, I read on TV Tropes that the original coding for Sonic CD is lost, which is why it was left out of the Sonic Mega Collection. And it was said that in order for it to be included on the Sonic Gems Collection, they used a hack of the PC version. And the current digital release is completely recoded.
But I can't remember where on TV Tropes I read it. I thought it was on either the Sonic CD page or Keep Circulating the Tapes, but when I looked I couldn't find that info (unless maybe it was deleted, but I'd have to check history for that). Today I did a google search asking "did Sega lose the coding for Sonic CD", with no results I could find (though I found the Sonic Wiki entry on the game, which speculates that the PC version was most likely used because it'd be hard to process a Sega CD game onto the Game Cube).
So... Anybody know if Sega actually did lose the coding, or if the information I found might have been wrong? I wish i could remember where on TV Tropes I saw the info.