Errm, all this discussion about PBL and loading from NAND is interesting, but doesn't really answer my original question :-)
I'll be more specific: Where does the Amstrad firmware sit in the NAND flash? Does the 'linux.pbl' build deliberately avoid the amstrad code, or could it in theory wipe it out...? What are the memory ranges available?
Could someone chuck an annotated memory map diagram on the wiki perhaps?