Yes, this is enough. The point is to have original factory firmware on NAND to ensure that you have a working device tree.
Run LE from SD. When you take it out, your box will boot into Android.
I think the issue might be that you had wrong default framebuffer resolution in device tree. For the boxes with issue this was fixed in .003 aml_autoscript but you'd have to re-apply the script. Now that you applied the script for SD installation, NAND version may run OK. I am aware that issues are still there. I hope they can be addressed at least to some degree when I apply updates from latest Amlogic kernel release.
Can this run from a USB? I am not even sure how to run LE from a SD. As of now, I am having trouble with space issues. The box only has 5Gigs and it is already full! So it is running like crap. I would like somehow to use this with a larger USB flash drive, like I did with a Raspberry Pi and USB.