Marc,
In an effort to keep our initial release of Android on schedule we did not verify the NAND boot process. Because of this, we don't have documentation on it either. You may be able to get what you need from the open source community - Rowboat or others.
We will have NAND support and documentation in the next release - see our Software Roamap -
http://support.logicpd.com/downloads/1491/
Thanks!
Richard