There are four desktop images on the disc. They can easily be accessed by putting the disc into a PC, and navigating to the Extras directory in the root of the disc.

According to a Retro Gamer Magazine article, the Sonic World level in Sonic Jam was a prototype of Sonic Adventure, based on the development that had been done at the time for the Saturn. "Due to technical issues and the timing of the upcoming Dreamcast project... we then moved development for Sonic Adventure to the Dreamcast," said producer Takashi Iizuka.