Using an NTSC-U Dreamcast, I can't get the Japanese GET!! Colonies puzzle game (GD-ROM) to correctly boot. The game freezes at its very start (past the Dreamcast boot screens) with the Codebreaker demo disk (CD-R) with or without accessories (such as controller, VMU, or rumble pack). At that point, the screen is white with a thin gray vertical bar across the leftmost side of the screen. The game also freezes the Dreamcast at the 94% mark at the Utopia screen when using the Utopia Boot Disk (CD-R) with or without accessories even though Utopia correctly shows the disk's included disk art from the GD-ROM's files. The Dreamcast must then be cold-booted (power-cycled) to get it to work again. All other Japanese-region games work with this Dreamcast and either boot disk.
Please help. Any pertinent advice is appreciated. Any information about the GET!! Colonies game could be helpful as I want to see if it is "the game's fault" or if it is due to bit rot (even though the GD-ROM appears to be pristine with no noticeable damage on either side of the disk).