Doesn't NRGZ Rom require you to run a .cab to get the data working? I thought thats what I read in one of his threads.
Code
http://ppcgeeks.com/forum.ppcgeeks/showpost.php?p=931583&postcount=3
I think you need to use a dcd carrier cab, unless you already did that, then IDK...but I did see a lot of people having trouble with data on his rom