I probably should change the instrucitions too:
dd if=./ubcd/tools/linux/ubcd2usb/mbr.bin of=/dev/sdX bs=440 count=1
This will prevent that too many bytes are overwritten if mbr.bin would be longer than 440 bytes (it normally isn't).
How did you format your USB drive?
Did you make your filesystem on the whole drive (it looks like that) or did you create the filesystem on a partition of that drive?
Download Ultimate Boot CD v5.0
Use Parted Magic
for handling all partitioning task: http://partedmagic.com/