Sorry to hear bout your problems you're having dude that sux i had the same kind of troubles when i 1st set up my system with the NME 2.0 also.
question 1, are you using an original when you try to make a backup using XBC?
i ask this cuz if its a bad backup burn you wont be able to extract the image thru XBC, use the original it should come up fine, if not working still, go into your network devices and disable that drive wait a minute, then re-enable it. tho thats never happened to me im pretty sure a bad burn wont be able to be extracted thru XBC, just use the original.
2nd, if you are able to buy DL DVD+R discs from different brands do that, if you are able to just get singles or 3 packs of a few diff kinds i would say try it.
i went from using HP DL DVD+R 2.4x from 3 pack in jewel cases to the 15 pack spindles, couldnt get a single burn from the spindles to ever work properly, same brand of disc and look identical to eachother, but the spindle discs wont ever work, only the 3 pack that came in jewel cases worked perfect every time.
the NME 2.0 seems like it could of still used some working on before being released to market, but too late for that now, takes some time to get everything figured out to what will work for you so patience is nessesary, try a few different disk types, also im not sure what drive you have i have a Hitachi 79FK
that in order to boot up anything requires me to NOT have soldered the J1 jumper, if you put solder on that spot, try and remove it, when i did my original install i forgot to fill it with solder and my backups worked, when i realized i left that un filled i opened it all backup, and filled it, closed it all up, only to find out that it would no longer play either burns, or originals, removed the solder from the J1 jumper spot on the chip and everything went back to working fine again, like i said seems like the NME 2.0 has quite a few faults that should of been addressed before the chip went out for sale but it seems with some patience, trial and error will eventually lead you to success now that i know what kind of discs work for burning i get them every time no more coasters
i use SH-D162C w/kreon firmware
and pioneer 111D for burns
for extractions i use XBC and then use SS merge and NME associator to turn images into NME compatable and burn with IMG burn