KallistiOS is a library for the Dreamcast (not at all piracy related at all). Unless you're planning on doing some programming for the Dreamcast, its pretty much pointless. If you are planning on programming for the Dreamcast, I'd suggest learning C pretty well before hand. Once you know your way around C, using KallistiOS should be pretty easy.
Sidenote: The reason the other topic was locked is that we do not allow discussion of "backups" here. Since changing the textures in a game for the Dreamcast requires a "backup" of the disc, it falls under that policy. Also, having a CDI of a game pretty much guarantees that you probably didn't dump it yourself (especially if you don't know how to change files in it), so it would be completely illegal...
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