I can't help with non-resident CCW, but open carry is legal without a permit and you only have to register handguns in Clark County/Las Vegas proper. Check reciprocity if you have a NH or Utah permit.
ETA: hrm, no dice on reciprocity in these parts or Utah.
My experience, though it goes back a long time, is that you can do pretty much anything you want in NV but when you break the law they crush you. By this I mean that almost everything is legal, but the things that aren't legal are felonies.