It is a gross misdemeanor to carry a dirk, dagger, or machete concealed, or to carry a belt buckle knife.
It is a class C felony to conceal other weapons, including specifically firearms.
Yes, Nevada does require an 8 hour training course to get the Nevada permit. If you are a Nevada resident, you will need a Nevada permit to carry concealed even if Nevada recognizes your other state permits if you are a non-resident. Nevada doesn't recognize the Oregon permit, even for non-residents.
If NRS 244.364, NRS 268.418, and NRS 269.222 meant anything, localities wouldn't be able to regulate firearms except the discharge of them, and Clark County registration would remain intact.
However, according to the current Office of Nevada Attorney General website, these laws don't mean anything.