Multi-Distro boot DVD with SystemRescueCD 2.8.0 fails to boot the SRCD portion

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http://unix.stackexchange.com – I'm trying to create a multi-distro mutli-boot dvd image containing (amongst others) the SystemRescueCD iso. I'm using GRUB as the boot loader and I've managed to get most of the other ISOs booting fine (testing in VirtualBox before I burn to disc). But the RescueCD iso fails to boot fully and just drops me out to a mini console. It starts to load the kernel image and initram.igz okay, then after it prompts for the keymap it attempts to locate the sysrcd.dat file (which contains the file system image) by trying to mount /dev/sr0 and /dev/sd0 but this is the wrong place. I need it to mount /de (HowTos)