I downloaded SystemRescueCd 0.4.3, and used the instructions under install SystemRescueCd on an USB stick to install it from Windows.
After solving some little issues, I made the USB load the syslinux bootloader, but at this stage, the "boot:" prompt was displayed without any additional text.
Trying to boot default, or write down "vmlinuz2" or "rescuecd" or any other thing left to "linux kernel not found" message. I checked and re-checked the file locations, and nothing.
I also tried http://www.sysresccd.org/Howto_install-usb-stick and nothing
Then I remembered something: all linux bootloaders I know (I mostly know grub) have a limitation: they only see things in the first XXMB of the disk. I don't remember the exact number, but I think it's 128MB.
The manual says
1. Copy "syslinux/syslinux.cfg" to the root of the USB device
2. Copy "sysrcd.dat" to the root of the USB device
3. Copy files in the "isolinux" directory to the root of the USB device
4. Copy the "bootdisk" directory to the root of the USB device
I think this manual was done in times in which SystemRescueCD was about 120MB size, but now "sysrcd.dat" is 140MB size. If you copy first this file and AFTER that the kernel images and initrd images, these will drop out of the range of the boot loader, so I modified the procedure to do the same but in different order
1. Copy isolinux files
2. Copy bootdisk files
3. Copy syslinux.cfg and sysrcd.dat
4. syslinux -ma e: (my pendrive was at e:)
Voilá... the disk booted perfect!!!!
Hope this helps someone :) see you around.