The boot messages are not on the HDMI screen, they are from the Cubie serial port. You need to connect a TTL-serial to USB cable to the Cubie board and monitor it with a terminal program. The instructions are here:
http://linux-sunxi.org/Cubieboard/TTLWhen you initially partition your card, you have to place the partition and file system after sector 2048, so it does not get overwritten by the dd commands. I used FAT because it was easy. I also tried ext2, but ext2 is not supported natively on Mac OS X and the ext2 file system I created did not work on the Cubie.
What do you get if you examine your SD card with fdisk, before and after copying sunxi-spl.bin and u-boot.bin?
I did not create a separate boot partition, and I did not place uCore, uEnv.txt and boot.scr in a /boot folder.