really daddyj? i was under the impression that it just wouldn't find the shadowc image, wouldn't load it...then would continue about its business as normal. then you can just use the create shadow c application and it will take care of it for you. (somebody with more info on nkpatcher could perhaps tell us more about that though?)
either way, if you are loading a dash from c and your xbox loaded a shadowc image that doesn't have your dashboard on it...you are going to need to get rid of that shadowc.img in order to get your xbox to work. otherwise it's simply not going to boot and you're stuck.
basically nkpatcher is compiled to load shadowc from somewhere, and it will always attempt to load it from there, regardless of whether you have created a shadowc or not. by default, it is from the E drive. basically what would happen was that you'd boot your xbox, it would use the real c to run nkpatcher (everything going fine) then it would switch your c drive with the shadowc drive. it would THEN try to load the dashboard from C, and since it wasn't there, it would crap out. reformatting the C drive wasn't doing anything because the C drive was working fine, it was the shadowc.img file that had the problem, and you couldn't touch that by formatting C with xboxhdm (because the image file was on E). make sense? i can't really explain it any better than that... and if you recompile nkpatcher (or hex edit it? i don't even know if that's possible but whatever) to look for shadowc in a different place, then it would only look there and not in E.
*SIGH* i still get a kick out of people not believing me...do i have stupid written on my forehead? on second though, don't answer that...