Allright, I'm feeling really dumb by now.
First I tried building a new image from my very first NAND with xeBuild GUI, then flashing with Rawflash v4
Still, E71 at NXE
Then I tried the Bestpig app to create the image, and flash it with Rawflash; now showing write errors (bad blocks) at 0128, 0129, 012a, 0143 and 03ff. Yes two more than before.
JTAG tool didn't really work for me, my Windows7 64 bit doesn't like this app, giving me all sorts of errors.
I feel the problem lies with writing the image to the nand... the created image must be right yes?
Crap, so many settings I don't know nothing about, am about to give up and buy me a new Slim RGH
BTW FSD still booting fine...